ALPHA METALLURGICAL RESOURCES, INC., 10-K filed on 3/7/2022
Annual Report
v3.22.0.1
Cover - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Feb. 28, 2022
Jun. 30, 2021
Cover [Abstract]      
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2021    
Current Fiscal Year End Date --12-31    
Document Transition Report false    
Entity File Number 001-38735    
Entity Registrant Name ALPHA METALLURGICAL RESOURCES, INC.    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 81-3015061    
Entity Address, Address Line One 340 Martin Luther King Jr. Blvd.    
Entity Address, City or Town Bristol    
Entity Address, State or Province TN    
Entity Address, Postal Zip Code 37620    
City Area Code 423    
Local Phone Number 573-0300    
Title of 12(b) Security Common Stock, par value $0.01 per share    
Trading Symbol AMR    
Security Exchange Name NYSE    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Accelerated Filer    
Entity Small Business true    
Entity Emerging Growth Company false    
ICFR Auditor Attestation Flag true    
Entity Shell Company false    
Entity Public Float     $ 270
Entity Common Stock, Shares Outstanding   18,532,992  
Documents Incorporated by Reference Part III incorporates certain information by reference from the registrant’s definitive proxy statement for the 2022 annual meeting of stockholders (the “Proxy Statement”), which will be filed no later than 120 days after the close of the registrant’s fiscal year ended December 31, 2021.    
Entity Central Index Key 0001704715    
Document Fiscal Year Focus 2021    
Document Fiscal Period Focus FY    
Amendment Flag false    
v3.22.0.1
Audit Information
 12 Months Ended
Dec. 31, 2021
Audit Information [Abstract]  
Auditor Name RSM US LLP
Auditor Location Atlanta, Georgia
Auditor Firm ID 49
v3.22.0.1
Consolidated Statements of Operations - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Revenues:    
Coal revenues $ 2,252,597 $ 1,413,124
Other revenues 5,989 3,063
Total revenues 2,258,586 1,416,187
Costs and expenses:    
Cost of coal sales (exclusive of items shown separately below) 1,679,742 1,281,011
Depreciation, depletion and amortization 110,047 139,885
Accretion on asset retirement obligations 26,520 26,504
Amortization of acquired intangibles, net 13,244 9,214
Asset impairment and restructuring (561) 83,878
Selling, general and administrative expenses (exclusive of depreciation, depletion and amortization shown separately above) 63,901 57,356
Total other operating loss (income):    
Mark-to-market adjustment for acquisition-related obligations 19,525 (8,750)
Other income (10,972) (2,223)
Total costs and expenses 1,901,446 1,586,875
Income (loss) from operations 357,140 (170,688)
Other (expense) income:    
Interest expense (69,654) (74,528)
Interest income 334 7,027
Equity loss in affiliates (4,149) (3,473)
Miscellaneous income (loss), net 6,867 (1,972)
Total other expense, net (66,602) (72,946)
Income (loss) from continuing operations before income taxes 290,538 (243,634)
Income tax (expense) benefit (3,609) 2,164
Net income (loss) from continuing operations 286,929 (241,470)
Discontinued operations:    
Income (loss) from discontinued operations before income taxes 1,660 (205,429)
Income tax benefit from discontinued operations 201 0
Income (loss) from discontinued operations 1,861 (205,429)
Net income (loss) $ 288,790 $ (446,899)
Basic income (loss) per common share:    
Income (loss) from continuing operations (in dollars per share) $ 15.56 $ (13.20)
Income (loss) from discontinued operations (in dollars per share) 0.10 (11.22)
Net income (loss) (in dollars per share) 15.66 (24.42)
Diluted income (loss) per common share:    
Income (loss) from continuing operations (in dollars per share) 15.20 (13.20)
Income (loss) from discontinuing operations (in dollars per share) 0.10 (11.22)
Net income (loss) (in dollars per share) $ 15.30 $ (24.42)
Weighted average shares - basic (in shares) 18,441,175 18,298,362
Weighted average shares - diluted (in shares) 18,871,682 18,298,362
v3.22.0.1
Consolidated Statements of Comprehensive Income (Loss) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Statement of Other Comprehensive Income [Abstract]    
Net income (loss) $ 288,790 $ (446,899)
Employee benefit plans:    
Current period actuarial gain (loss) 47,461 (60,647)
Income tax 0 0
Current period actuarial (loss) gain, net of income tax 47,461 (60,647)
Less: reclassification adjustments for amounts reclassified to earnings due to amortization of net actuarial loss and settlements 6,021 7,278
Income tax 0 0
Less: reclamation adjustments for amounts reclassified to earnings due to amortization of net actuarial (gain) loss and settlements, net of income tax 6,021 7,278
Total other comprehensive income (loss), net of tax 53,482 (53,369)
Total comprehensive income (loss) $ 342,272 $ (500,268)
v3.22.0.1
Consolidated Balance Sheets - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Current assets:    
Cash and cash equivalents $ 81,211 $ 139,227
Trade accounts receivable, net of allowance for doubtful accounts of $393 and $293 as of December 31, 2021 and 2020, respectively 489,241 145,670
Inventories, net 129,382 108,051
Prepaid expenses and other current assets 47,690 106,252
Current assets - discontinued operations 462 10,935
Total current assets 747,986 510,135
Property, plant, and equipment, net of accumulated depreciation and amortization of $443,856 and $382,423 as of December 31, 2021 and 2020, respectively 362,218 363,620
Owned and leased mineral rights, net of accumulated depletion and amortization of $52,444 and $35,143 as of December 31, 2021 and 2020, respectively 444,302 463,250
Other acquired intangibles, net of accumulated amortization of $34,221 and $25,700 as of December 31, 2021 and 2020, respectively 74,197 88,196
Long-term restricted cash 89,426 96,033
Other non-current assets 131,057 149,382
Non-current assets - discontinued operations 8,526 9,473
Total assets 1,857,712 1,680,089
Current liabilities:    
Current portion of long-term debt 2,989 28,830
Trade accounts payable 90,090 58,413
Acquisition-related obligations - current 22,405 19,099
Accrued expenses and other current liabilities 174,607 140,406
Current liabilities - discontinued operations 5,838 12,306
Total current liabilities 295,929 259,054
Long-term debt 445,562 553,697
Acquisition-related obligations - long-term 19,000 20,768
Workers’ compensation and black lung obligations 208,193 230,081
Pension obligations 159,930 218,671
Asset retirement obligations 132,013 140,074
Deferred income taxes 317 480
Other non-current liabilities 26,176 28,072
Non-current liabilities - discontinued operations 23,683 29,090
Total liabilities 1,310,803 1,479,987
Commitments and Contingencies (Note 22)
Stockholders’ Equity    
Preferred stock - par value $0.01, 5.0 million shares authorized, none issued 0 0
Common stock - par value $0.01, 50.0 million shares authorized, 20.8 million issued and 18.4 million outstanding at December 31, 2021 and 20.6 million issued and 18.3 million outstanding at December 31, 2020 208 206
Additional paid-in capital 784,743 779,424
Accumulated other comprehensive loss (58,503) (111,985)
Treasury stock, at cost: 2.4 million shares at December 31, 2021 and 2.3 million shares at December 31, 2020 (107,800) (107,014)
Accumulated deficit (71,739) (360,529)
Total stockholders’ equity 546,909 200,102
Total liabilities and stockholders’ equity $ 1,857,712 $ 1,680,089
v3.22.0.1
Consolidated Balance Sheets - Parenthetical - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Statement of Financial Position [Abstract]    
Allowance for doubtful accounts $ 393 $ 293
Less accumulated depreciation, depletion and amortization 443,856 382,423
Owned and leased mineral rights, accumulated depletion and amortization 52,444 35,143
Other acquired intangibles, accumulated amortization $ 34,221 $ 25,700
Preferred stock, par value (in dollars per share) $ 0.01 $ 0.01
Preferred stock, shares authorized (in shares) 5,000,000.0 5,000,000.0
Preferred stock, shares issued (in shares) 0 0
Common stock, par value (in dollars per share) $ 0.01 $ 0.01
Common stock, shares authorized (in shares) 50,000,000.0 50,000,000.0
Common stock, shares issued (in shares) 20,800,000 20,600,000
Common stock, shares outstanding (in shares) 18,400,000 18,300,000
Treasury stock, shares at cost (in shares) 2,400,000 2,300,000
v3.22.0.1
Consolidated Statements of Cash Flows - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Operating activities:    
Net income (loss) $ 288,790 $ (446,899)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:    
Depreciation, depletion and amortization 110,047 151,455
Amortization of acquired intangibles, net 13,244 10,075
Accretion of acquisition-related obligations discount 1,258 3,342
Amortization of debt issuance costs and accretion of debt discount 12,338 14,772
Mark-to-market adjustment for acquisition-related obligations 19,525 (8,750)
Loss on sale of business 0 36,113
Gain on disposal of assets, net (9,911) (2,401)
Accretion on asset retirement obligations 26,520 30,658
Employee benefit plans, net (1,751) 14,439
Deferred income taxes (163) 33,123
Asset impairment and restructuring (561) 256,518
Stock-based compensation 5,315 4,896
Equity loss in affiliates 4,149 3,473
Other, net (6,570) (5,972)
Changes in operating assets and liabilities    
Trade accounts receivable, net (336,240) 91,190
Inventories, net (21,331) 48,689
Prepaid expenses and other current assets 61,581 28,152
Deposits 26,853 (17,926)
Other non-current assets (250) (6,753)
Trade accounts payable 25,154 (28,620)
Accrued expenses and other current liabilities 15,961 15,428
Acquisition-related obligations (18,121) (32,560)
Asset retirement obligations (16,306) (19,375)
Other non-current liabilities (24,588) (43,831)
Net cash provided by operating activities 174,943 129,236
Investing activities:    
Capital expenditures (83,300) (153,990)
Proceeds on disposal of assets 8,224 4,023
Cash paid on sale of business 0 (52,192)
Capital contributions to equity affiliates (6,677) (3,443)
Purchases of investment securities (17,985) (21,129)
Maturity of investment securities 13,265 16,685
Other, net (3,382) 77
Net cash used in investing activities (89,855) (209,969)
Financing activities:    
Proceeds from borrowings on long-term debt 0 57,500
Repurchases of long-term debt (18,415) 0
Principal repayments of long-term debt (119,097) (76,491)
Principal repayments of financing lease obligations (2,064) (3,176)
Debt issuance costs (6,683) 0
Common stock repurchases and related expenses (786) (209)
Net cash used in financing activities (147,045) (22,376)
Net decrease in cash and cash equivalents and restricted cash (61,957) (103,109)
Cash and cash equivalents and restricted cash at beginning of period 244,571 347,680
Cash and cash equivalents and restricted cash at end of period 182,614 244,571
Supplemental cash flow information:    
Cash paid for interest 63,061 49,294
Cash paid for income taxes 176 5
Cash received for income tax refunds 64,498 68,801
Supplemental disclosure of noncash investing and financing activities:    
Financing leases and capital financing - equipment 787 4,411
Accrued capital expenditures 9,964 7,493
Reconciliation of Cash and Cash Equivalents and Restricted Cash    
Cash and cash equivalents 81,211 139,227
Short-term restricted cash 11,977 9,311
Long-term restricted cash 89,426 96,033
Total cash and cash equivalents and restricted cash shown in the Consolidated Statements of Cash Flows $ 182,614 $ 244,571
v3.22.0.1
Consolidated Statements of Stockholders' Equity - USD ($)
$ in Thousands
Total
Cumulative Effect, Period of Adoption, Adjustment
Common Stock
Additional Paid-in Capital
Accumulated Other Comprehensive (Loss) Income
Treasury Stock at Cost
Retained Earnings (Accumulated Deficit)
Retained Earnings (Accumulated Deficit)
Cumulative Effect, Period of Adoption, Adjustment
Beginning balance at Dec. 31, 2019 $ 696,122 $ (440) $ 205 $ 775,707 $ (58,616) $ (107,984) $ 86,810 $ (440)
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Net income (loss) (446,899)           (446,899)  
Other comprehensive income (loss), net (53,369)       (53,369)      
Stock-based compensation and net issuance of common stock for share vesting 3,718   1 3,717        
Common stock reissuances, repurchases and related expenses 970         970    
Ending balance at Dec. 31, 2020 200,102   206 779,424 (111,985) (107,014) (360,529)  
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Net income (loss) 288,790           288,790  
Other comprehensive income (loss), net 53,482       53,482      
Stock-based compensation and net issuance of common stock for share vesting 5,315   2 5,313        
Common stock reissuances, repurchases and related expenses (786)         (786)    
Warrant exercises 6     6        
Ending balance at Dec. 31, 2021 $ 546,909   $ 208 $ 784,743 $ (58,503) $ (107,800) $ (71,739)  
v3.22.0.1
Business and Basis of Presentation
 12 Months Ended
Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Business and Basis of Presentation Business and Basis of Presentation
Business
Alpha Metallurgical Resources, Inc. (“Alpha” or the “Company”), previously named Contura Energy, Inc., is a Tennessee-based mining company with operations across Virginia and West Virginia. With customers across the globe, high-quality reserves and significant port capacity, Alpha is a leading U.S. supplier of metallurgical coal products for the steel industry.
The Company was formed to acquire and operate certain of Alpha Natural Resources, Inc.’s core coal operations, as part of the Alpha Natural Resources, Inc. bankruptcy reorganization. The Company began operations on July 26, 2016 and currently operates mines in the Central Appalachia region.
A merger with ANR, Inc. and Alpha Natural Resources Holdings, Inc. (together, the "Merger Companies”) was completed on November 9, 2018 (the “Merger”) pursuant to terms of the definitive merger agreement (the “Merger Agreement”). Upon the consummation of the transactions contemplated by the Merger Agreement, the Company began trading on the New York Stock Exchange under the ticker “CTRA.”

Effective February 1, 2021, the Company changed its corporate name from Contura Energy, Inc. to Alpha Metallurgical Resources, Inc. to more accurately reflect its strategic focus on the production of metallurgical coal. Following the effectiveness of its name change, the Company’s ticker symbol on the New York Stock Exchange changed from “CTRA” to “AMR” effective on February 4, 2021.

Basis of Presentation

Together, the consolidated balance sheets and consolidated statements of operations, comprehensive income (loss), cash flows and stockholders’ equity for the Company are referred to as the “Financial Statements.” The Financial Statements are also referred to as “Consolidated” and references across periods are generally labeled “Balance Sheets,” “Statements of Operations,” and “Statements of Cash Flows.” The Company’s former Northern Appalachia (“NAPP”) operations results of operations and financial position are reported as discontinued operations in the Consolidated Financial Statements. Refer to Note 3 for further information on discontinued operations.
The Consolidated Financial Statements include all wholly owned subsidiaries’ results of operations for the years ended December 31, 2021 and 2020. All significant intercompany transactions have been eliminated in consolidation.

The accompanying Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”).
Reclassifications
Certain amounts in the prior year Consolidated Statements of Cash Flows have been reclassified to conform to the current year presentation.

Liquidity Risks and Uncertainties

The Company believes it will have sufficient liquidity to meet its working capital requirements, anticipated capital expenditures, debt service requirements, acquisition-related obligations, and reclamation obligations for the 12 months subsequent to the issuance of these financial statements. However, the Company may need to raise additional funds if market conditions deteriorate and may not be able to do so in a timely fashion, or at all. The Company relies on a number of assumptions in budgeting for future activities. These include the costs for mine development to sustain capacity of its operating mines, cash flows from operations, effects of regulation and taxes by governmental agencies, mining technology improvements and reclamation costs. These assumptions are inherently subject to significant business, political, economic, regulatory, environmental and competitive uncertainties, pending and existing climate-related initiatives, contingencies and risks, all of which are difficult to predict and many of which are beyond the Company’s control. Therefore, the Company’s cash on hand and from future operations will be subject to any significant changes in these assumptions.
COVID-19 Pandemic

In the first quarter of 2020, the COVID-19 virus was declared a pandemic by the World Health Organization. The COVID-19 pandemic has had negative impacts on the Company’s business, results of operations, financial condition and cash flows. The full extent of the impact of the COVID-19 pandemic on the Company’s operational and financial performance will depend on certain developments, including the duration and spread of the outbreak, its impact on its customers and suppliers and the range of governmental and community reactions to the pandemic, which are still uncertain and still cannot be fully predicted.
v3.22.0.1
Summary of Significant Accounting Policies
 12 Months Ended
Dec. 31, 2021
Accounting Policies [Abstract]  
Summary of Significant Accounting Policies Summary of Significant Accounting Policies
Use of Estimates

The preparation of the Company’s Consolidated Financial Statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the Consolidated Financial Statements and the reported amounts of revenues and expenses during the reporting period. Significant items subject to such estimates and assumptions include inventories; mineral reserves and resources; long-lived asset impairments; reclamation obligations; post-employment and other employee benefit obligations; useful lives, depletion and amortization; reserves for workers’ compensation and black lung claims; deferred income taxes; income taxes refundable and receivable; reserves for contingencies and litigation; fair value of financial instruments; and fair value adjustments for acquisition accounting. Estimates are based on facts and circumstances believed to be reasonable at the time; however, actual results could differ from those estimates.

Cash and Cash Equivalents

 Cash and cash equivalents consist of cash held with reputable depository institutions and highly liquid, short-term investments, such as highly-rated money market funds, with original maturities of three months or less. Cash and cash equivalents are stated at cost, which approximates fair value.

Restricted Cash

Amounts included in restricted cash represent cash deposits primarily invested in interest-bearing accounts that are restricted as to withdrawal as required by certain agreements entered into by the Company and provide collateral to secure the certain obligations which have been written on the Company’s behalf. Refer to Note 22 for further information.

Restricted Investments

Restricted investments consist of Federal Deposit Insurance Company (“FDIC”) insured certificates of deposit, mutual funds, and U.S. treasury bills classified as either trading securities or held-to-maturity securities that are restricted as to withdrawal as required by certain agreements entered into by the Company and provide collateral to secure certain obligations which have been written on the Company’s behalf.

Trading securities are recorded initially at cost and are adjusted to fair value at each reporting period with unrealized gains and recorded in current period earnings or loss. Held-to-maturity securities are recorded at amortized cost with interest income recorded in current period earnings. Given the nature of the underlying investments, the Company does not expect any credit losses and has not recorded any credit losses with respect to its held-to-maturity portfolio. Refer to Note 22 for further information.

Deposits

Deposits represent cash deposits held at third parties as required by certain agreements entered into by the Company to provide cash collateral to secure the following obligations which have been written on the Company’s behalf. Refer to Note 22 for further information.

Trade Accounts Receivable and Allowance for Doubtful Accounts
Trade accounts receivable are recorded at their invoiced amounts and do not bear interest. The Company markets its coal primarily to domestic and international steel producers and electric utilities in the United States. Credit is extended based on an evaluation of a customer’s financial condition, including a review of third-party credit score information. Collateral is generally not required. Accounts receivable balances are monitored against approved credit limits. Credit limits are monitored and adjusted as considered necessary based on changes to a customer’s credit profile. If a customer’s credit deteriorates, the Company may reduce credit risk exposure by reducing credit limits, obtaining letters of credit, obtaining credit insurance, or requiring pre-payment for shipments. Credit losses have historically not been material. Account balances are written-off against the allowance after all means of collection have been exhausted and the potential for recovery is considered remote. Refer to Note 23 for further information.

Inventories

Coal is reported as inventory at the point in time the coal is extracted from the mine. Raw coal represents coal stockpiles that may be sold in current condition or may be further processed prior to shipment to a customer. Saleable coal represents coal stockpiles that require no further processing prior to shipment to a customer.

Coal inventories are valued at the lower of average cost or net realizable value. The cost of coal inventories is determined based on the average cost of production, which includes labor, supplies, equipment costs, operating overhead, depreciation, and other related costs. Net realizable value considers the projected future sales price of the product, less estimated preparation and selling costs. Material and supplies inventories are valued at average cost, less an allowance for obsolete and surplus items. Refer to Note 7 for further information.

Discontinued Operations

In accordance with Accounting Standards Codification (“ASC”) 205-20-45, the Company treats a disposal transaction as a discontinued operation when the disposal of a component or group of components represents a strategic shift that will have a major effect on the Company’s operations and financial results. In the period in which the discontinued operations criteria are met, the assets and liabilities of the discontinued operations are separately presented on the Company's Consolidated Balance Sheets and the results of operations, including any gain or loss recognized, is reclassified to discontinued operations on the Company’s Consolidated Statement of Operations. Refer to Note 3 for further information.

Deferred Longwall Move Expenses

The Company deferred the direct costs, including labor and supplies, associated with moving longwall equipment, the related equipment refurbishment costs, costs to drill vent holes and plug existing gas wells in advance of the longwall panel associated with its former NAPP operations included in discontinued operations during the year ending December 31, 2020. Refer to Note 3 for further information. These deferred costs were amortized on a units-of-production basis into cost of coal sales over the life of the related panel of coal mined by the longwall equipment.

Advanced Mining Royalties

Lease rights to coal reserves are often acquired in exchange for royalty payments. Advance mining royalties are advance payments made to lessors under terms of mineral lease agreements that are recoupable against future production royalties. These advance payments are deferred and charged to operations as the coal reserves are mined. The Company regularly reviews recoverability of advance mining royalties and establishes or adjusts the allowance for advance mining royalties as necessary using the specific identification method. Advance royalty balances are generally charged off against the allowance when they are no longer recoupable. Refer to Note 11 for further information.

Property, Plant, and Equipment, Net

Costs for mine development incurred to expand capacity of operating mines or to develop new mines are capitalized and charged to operations on the units-of-production method over the estimated proven and probable reserve tons directly benefiting from the capital expenditures. Mine development costs include costs incurred for site preparation and development of the mines during the development stage less any incidental revenue generated during the development stage. Mining equipment, buildings, and other fixed assets are stated at cost and depreciated on a straight-line basis over estimated useful lives ranging from one to 25 years. Leasehold improvements are amortized using the straight-line method, over the shorter of the estimated
useful lives or term of the lease. Major repairs and betterments that significantly extend original useful lives or improve productivity are capitalized and depreciated over the period benefited. Maintenance and repairs are expensed as incurred. When equipment is retired or disposed, the related cost and accumulated depreciation are removed from the respective accounts and any profit or loss on disposal is recognized in other (income) expense in the Company’s Consolidated Statements of Operations. Refer to Note 10 for further information.

Owned and Leased Mineral Rights

Owned and leased mineral rights, net of accumulated depletion and amortization, for the years ended December 31, 2021 and 2020 were $444,302 and $463,250, respectively, and are reported in assets in the Company’s Consolidated Balance Sheets. These amounts include $10,354 and $10,491 of asset retirement obligation assets, net of accumulated amortization, associated with active mining operations for the years ended December 31, 2021 and 2020, respectively. During the year ended December 31, 2020, the Company recorded a long-lived asset impairment which reduced the carrying value of owned and leased mineral rights, net, by $41,579. Refer to Note 8 for further information on long-lived asset impairment.

Costs to obtain owned and leased mineral rights are capitalized and amortized to operations as depletion expense using the units-of-production method. Only proven and probable reserves are included in the depletion base. Depletion expense is included in depreciation, depletion and amortization in the accompanying Consolidated Statements of Operations and was $23,541 and ($13,746) for the years ended December 31, 2021 and 2020, respectively.

Depletion expense for the years ended December 31, 2021 and 2020 includes an expense of $5,782 and a credit of ($34,377), respectively, related to revisions to asset retirement obligations. Refer to Note 16 for further disclosures related to asset retirement obligations.

Leases

In accordance with ASC 842, the Company recognizes right of use assets and lease liabilities on the Consolidated Balance Sheets for all leases with a term longer than 12 months. Some of these leases include both lease and non-lease components which are accounted for as a single lease component as the Company has elected the practical expedient to combine these components for all leases. The discount rates used to determine the present value of the lease assets and liabilities are based on the Company’s incremental borrowing rate at the lease commencement date and commensurate with the remaining lease term. As the rates implicit in most of the Company’s leases are not readily determinable, the Company uses a collateralized incremental borrowing rate based on the information available at the lease commencement date in determining the present value of future payments. The Company uses the portfolio approach and groups leases by short-term and long-term categories, applying the corresponding incremental borrowing rates to these categories of leases. For leases with a term of 12 months or less, no right of use assets or liabilities are recognized on the Consolidated Balance Sheets and the Company recognizes the lease expense on a straight-line basis over the lease term. Additionally, the Company recognizes variable lease payments as an expense in the period incurred. The Company has elected to show net instead of gross amounts for right-of-use assets and liabilities within its Consolidated Statements of Cash Flows. Refer to Note 12 for further information.

Acquired Intangibles

The Company has recognized assets for acquired above market-priced coal supply agreements and acquired mine permits and liabilities for acquired below market-priced coal supply agreements. The coal supply agreements were valued based on the present value of the difference between the expected net contractual cash flows based on the stated contract terms and the estimated net contractual cash flows derived from applying forward market prices at the Merger or acquisition date for new contracts of similar terms and conditions. The acquired mine permits were valued based on the replacement cost and lost profits method as of the Merger date. The balances and respective Consolidated Balance Sheets classifications of such assets and liabilities as of December 31, 2021 and 2020, net of accumulated amortization, are set forth in the following tables:

December 31, 2021
Assets (1)
Liabilities (2)
Net Total
Coal supply agreements, net$— $— $— 
Acquired mine permits, net74,197 — 74,197 
Total$74,197 $— $74,197 
December 31, 2020
Assets (1)
Liabilities (2)
Net Total
Coal supply agreements, net$— $(327)$(327)
Acquired mine permits, net88,196 — 88,196 
Total$88,196 $(327)$87,869 
(1) Included within Other acquired intangibles, net of accumulated amortization, on the Company’s Consolidated Balance Sheets.
(2) Included within Other non-current liabilities on the Company’s Consolidated Balance Sheets.

During the year ended December 31, 2020, the Company recorded long-lived asset impairments which reduced the carrying value of acquired mine permits, net, by $21,144. Refer to Note 8 for further information.

The acquired mine permits are amortized over the estimated life of the associated mine. The coal supply agreement assets and liabilities were amortized over the actual number of tons shipped over the life of each contract. The following table details the amortization of mine permits acquired as a result of the Merger and the amortization of above-market and below-market coal supply agreements.
December 31,
20212020
Amortization of mine permits (1)
$13,571 $14,887 
Amortization of above-market coal supply agreements$— $18 
Amortization of below-market coal supply agreements(327)(5,691)
Net income (1)
$(327)$(5,673)
(1) Included within amortization of acquired intangibles, net in the Consolidated Statements of Operations.


Future net amortization expense related to acquired intangibles is expected to be as follows:  
2022$11,749 
20238,079 
20246,728 
20256,723 
20266,196 
Thereafter34,722 
Total net future amortization expense$74,197 

Asset Impairment

Long-lived assets, such as property, plant, and equipment, mineral rights, and acquired intangibles subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or asset groups may not be recoverable. Recoverability of assets or asset groups to be held and used is measured by a comparison of the carrying amount of an asset or asset group to the estimated undiscounted future cash flows expected to be generated by the asset or asset group. Long-lived assets located in a close geographic area are grouped together for purposes of impairment testing when, after considering revenue and cost interdependencies, circumstances indicate the assets are used together to produce future cash flows. The Company’s asset groups generally consist of the assets and applicable liabilities of one or more mines and preparation plants and associated coal reserves for which cash flows are largely independent of cash flows of other mines, preparation plants, and associated coal reserves. If the carrying amount of an asset or asset group exceeds its estimated future cash flows, the potential impairment is equal to the amount by which the carrying amount of the asset or asset group exceeds the fair value of the asset or asset group. The Company estimates the fair value of an asset group generally using discounted cash flow analysis based on estimates of future sales volumes, coal prices, production costs, and a risk-adjusted cost of capital.
These estimates generally constitute unobservable Level 3 inputs under the fair value hierarchy. The amount of impairment, if any, is allocated to the long-lived assets on a pro-rata basis, except that the carrying value of the individual long-lived assets are not reduced below their estimated fair value. Refer to Note 8 for further information.

Asset Retirement Obligations

Minimum standards for mine reclamation have been established by various regulatory agencies and dictate the reclamation requirements at the Company’s operations. The Company’s asset retirement obligations consist principally of costs to reclaim acreage disturbed at surface operations and estimated costs to reclaim support acreage, treat mine water discharge, and perform other related functions at underground mines. The Company records these reclamation obligations at fair value in the period in which the legal obligation associated with the retirement of the long-lived asset is incurred. Changes to the liability at operations that are not currently being reclaimed are offset by increasing or decreasing the carrying amount of the related long-lived asset. Changes to the liability at operations that are currently being reclaimed are recorded to depreciation, depletion, and amortization. Over time, the liability is accreted and any capitalized cost is depreciated or depleted over the useful life of the related asset. To settle the liability, the obligation is paid, and any difference between the liability and the amount of cash paid is recorded within depreciation, depletion and amortization within the Consolidated Statements of Operations at the time the reclamation work is completed. The Company annually reviews its estimated future cash flows for its asset retirement obligations. Refer to Note 16 for further information.

Income Taxes

The Company recognizes deferred tax assets and liabilities using enacted tax rates for the effect of temporary differences between the book and tax bases of recorded assets and liabilities. Deferred tax assets are reduced by a valuation allowance if it is more likely than not that some portion or all of the deferred tax assets will not be realized. In evaluating its ability to recover deferred tax assets within the jurisdiction in which they arise, the Company considers all available positive and negative evidence, including the expected reversals of deferred tax liabilities, projected future taxable income, taxable income available via carryback to prior years, tax planning strategies, and results of recent operations. The Company assesses the realizability of its deferred tax assets, including scheduling the reversal of its deferred tax assets and liabilities, to determine the amount of valuation allowance needed. Scheduling the reversal of deferred tax asset and liability balances requires judgment and estimation. The Company believes the deferred tax liabilities relied upon as future taxable income in its assessment will reverse in the same period and jurisdiction and are of the same character as the temporary differences giving rise to the deferred tax assets that will be realized. Refer to Note 18 for further information.

Deferred Financing Costs

The costs to obtain new debt financing or amend existing financing agreements are generally deferred and amortized to interest expense over the life of the related indebtedness or credit facility using the effective interest method. Unamortized deferred financing costs are presented in the Consolidated Balance Sheets as a direct deduction from the carrying amount of the debt liability, consistent with debt discounts or premiums. Unamortized deferred financing costs associated with undrawn credit facilities are included in the Consolidated Balance Sheets within other non-current assets.

Revenue Recognition

In accordance with ASC 606 Revenue from Contracts with Customers (“ASC 606”), the Company measures revenue based on the consideration specified in a contract with a customer and recognizes revenue as a result of satisfying its promise to transfer goods or services in a contract with a customer using the following general revenue recognition five-step model: (1) identify the contract; (2) identify performance obligations; (3) determine transaction price; (4) allocate transaction price; and (5) recognize revenue. Freight and handling costs paid to third-party carriers and invoiced to coal customers are recorded as freight and handling costs and freight and handling fulfillment revenues within cost of coal sales and coal revenues, respectively. Refer to Note 4 for further information.

Workers’ Compensation and Pneumoconiosis (Black Lung) Benefits 

Workers’ Compensation

As of December 31, 2021, the Company’s subsidiaries generally utilize high-deductible insurance programs for workers’ compensation claims at its operations with the exception of certain subsidiaries in which the Company is a qualified self-insurer
for workers’ compensation obligations. The liabilities for workers’ compensation claims are estimates of the ultimate losses incurred based on the Company’s experience and include a provision for incurred but not reported losses. Adjustments to the probable ultimate liabilities are made annually based on an actuarial study and adjustments to the liability are recorded based on the results of this study. These short-term and long-term obligations are included in the Consolidated Balance Sheets within accrued expenses and other current liabilities and workers’ compensation and black lung obligations, respectively, with the related expected insurance receivables within prepaid expenses and other current assets and other non-current assets. As of December 31, 2021 and 2020, the workers’ compensation liability was net of a discount of $23,442 and $24,061, respectively, related to fair value adjustments associated with acquisition accounting. Refer to Note 19 for further information.

Black Lung Benefits

The Company is required by federal and state statutes to provide benefits to employees for awards related to black lung. As of December 31, 2021, certain of the Company’s subsidiaries are insured for black lung obligations by a third-party insurance provider and certain subsidiaries are self-insured for state black lung obligations. Certain other subsidiaries are self-insured for federal black lung benefits and may fund benefit payments through a Section 501(c)(21) tax-exempt trust fund. Charges are made to operations for black lung claims, as determined by an independent actuary at the present value of the actuarially computed liability for such benefits over the employee’s applicable term of service. The Company recognizes in its Consolidated Balance sheets the amount of the Company’s unfunded Accumulated Benefit Obligation (“ABO”) at the end of the year. The actuarial gains and losses recognized in accumulated other comprehensive income (loss) are amortized into components of net periodic benefit cost over the expected lifetime of active participants (the Company does not use a corridor method). These short-term and long-term obligations are included in the Consolidated Balance Sheets within accrued expenses and other current liabilities and workers’ compensation and black lung obligations, respectively. Refer to Note 19 for further information.

Pension

The Company is required to recognize the overfunded or underfunded status of a defined benefit pension plan as an asset or liability in its Consolidated Balance Sheets and to recognize changes in that funded status in the year in which the changes occur through other comprehensive (loss) income. The actuarial gains and losses recognized in accumulated other comprehensive income (loss) are amortized into components of net periodic benefit cost over the average future lifetime of participants expected to have benefits (the Company does not use a corridor method). The Company is required to measure plan assets and benefit obligations as of the date of the Company’s fiscal year-end Consolidated Balance Sheet and provide the required disclosures as of the end of each fiscal year. Refer to Note 19 for information.
Postretirement Life Insurance Benefits

As part of the Alpha Natural Resources, Inc. bankruptcy reorganization plan and the Retiree Committee Settlement Agreement, the Company assumed the liability for life insurance benefits for certain disabled and non-union retired employees. Provisions are made for estimated benefits based on annual evaluations prepared by independent actuaries. Adjustments to the probable ultimate liabilities are made annually based on an actuarial study and adjustments to the liability are recorded based on the results of this study. These obligations are included in the Consolidated Balance Sheets as Accrued expenses and other current liabilities and Other non-current liabilities. Refer to Note 19 for further information.

Net Income (Loss) per Share

 Basic net income (loss) per share is computed by dividing net income (loss) by the weighted-average number of outstanding common shares for the period. Diluted (loss) earnings per share reflects the potential dilution that could occur if instruments that may require the issuance of common shares in the future were settled and the underlying common shares were issued. Diluted (loss) earnings per share is computed by increasing the weighted-average number of outstanding common shares computed in basic earnings (loss) per share to include the additional common shares that would be outstanding after issuance and adjusting net income (loss) for changes that would result from the issuance. Only those securities that are dilutive are included in the calculation. In periods of loss, the number of shares used to calculate diluted earnings is the same as basic earnings per share. Refer to Note 6 for further information.

Stock-Based Compensation
The Company recognizes expense for stock-based compensation awards based on their grant-date fair value. The expense is recorded over the respective service period of the underlying award. Liability classified stock-based compensation awards are remeasured each reporting period at fair value until the award is settled. The Company recognizes forfeitures of stock-based compensation awards as they occur. Refer to Note 20 for further information.

Warrants

On July 26, 2016 (the “Initial Issue Date”), the Company issued 810,811 warrants, which are classified as equity instruments, each with an initial exercise price, as defined in the Series A Warrants Agreement (the “Warrants Agreement”), of $55.93 per share of common stock and exercisable for one share of the Alpha’s common stock, par value $0.01 per share. Pursuant to the Warrants Agreement, the warrants are exercisable for cash or on a cashless basis at any time from the Initial Issue Date until July 26, 2023, and no fractional shares shall be issued upon warrant exercises. The exercise price and the warrant share number will be adjusted in respect of certain dilutive events with respect to the common stock (namely, dividends or distributions on the common stock, share splits and combinations, above-market tender offers for common stock by the Company or a subsidiary thereof, and discounted issuances of common stock or rights or options to purchase common stock or securities convertible or exchangeable into common stock). Refer to Note 25 for subsequent event disclosures related to the Company’s share repurchase program. Additionally, in the case of any reorganization (i.e., a consolidation, merger, or sale of all or substantially all of the consolidated assets of Alpha) pursuant to which the common stock is converted into cash, securities or other property, the warrants would become exercisable for such property. As of December 31, 2021 and 2020, the exercise price was $46.911 per share and the warrant share number was equal to 1.15, as adjusted in respect to certain dilutive events with respect to the common stock during 2017 and 2018.
As of December 31, 2021, of the 810,811 warrants that were originally issued, 801,246 remained outstanding, with a total of 921,433 shares underlying the un-exercised warrants. For the year ended December 31, 2021, the Company issued 143 shares of common stock resulting from exercises of its Series A Warrants and, pursuant to the terms of the Warrants Agreement, withheld 17 of the issued shares in satisfaction of the warrant exercise price, which were subsequently reclassified as treasury stock. As of December 31, 2020, of the 810,811 warrants that were originally issued, 801,370 remained outstanding, with a total of 921,576 shares underlying the un-exercised warrants. For the year ended December 31, 2020, there were no warrant exercises.

Equity Method Investments

Investments in unconsolidated affiliates that the Company has the ability to exercise significant influence over, but not control, are accounted for under the equity method of accounting. Under the equity method of accounting, the Company records its proportionate share of the entity’s net income or loss at each reporting period in the Consolidated Statements of Operations in other (expense) income, with a corresponding entry to increase or decrease the carrying value of the investment. The carrying value of the Company’s equity method investments was $20,460 and $18,383 as of December 31, 2021 and 2020, respectively.

Recently Adopted Accounting Guidance

Business Combinations: In October 2021, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) 2021-08, Business Combinations (Topic 805), Accounting for Contract Assets and Contract Liabilities from Contracts with Customers (“ASU 2021-08”). This update requires an acquirer in a business combination to recognize and measure contract assets and contract liabilities from acquired contracts with customers using the revenue recognition guidance in ASC 606. This creates an exception to the general recognition and measurement principle in ASC 805, Business Combinations. The amendments in this update are intended to improve the accounting for acquired revenue contracts with customers in a business combination by addressing diversity in practice and certain inconsistencies. The update is effective for fiscal years beginning after December 15, 2022 and interim periods within those fiscal years for public business entities, with early adoption permitted. The Company adopted ASU 2021-08 during the fourth quarter of 2021. The adoption of this ASU did not have a material impact on the Company's Consolidated Financial Statements and related disclosures.

Presentation of Financial Statements: In August 2021, the FASB issued ASU 2021-06, Presentation of Financial Statements (Topic 205), Financial Services—Depository and Lending (Topic 942), and Financial Services—Investment Companies (Topic 946) (“ASU 2021-06”). This update amends certain SEC paragraphs from the Codification in response to the issuance of SEC Final Rule Nos. 33-10786, Amendments to Financial Disclosures About Acquired and Disposed Businesses, and 33-10835, Update of Statistical Disclosures for Bank and Savings and Loan Registrants. For all entities, the update is effective immediately. The Company adopted ASU 2021-06 during the third quarter of 2021. The adoption of this ASU did not
have a material impact on the Company's Consolidated Financial Statements and related disclosures.

Leases: In July 2021, the FASB issued ASU 2021-05, Leases (Topic 842) Lessors—Certain Leases with Variable Lease Payments (“ASU 2021-05”). The amendments in this update affect lessors with lease contracts that (1) have variable lease payments that do not depend on a reference index or a rate (“variable payments”) and (2) would have resulted in the recognition of a selling loss at lease commencement if classified as sales-type or direct financing. The amendments in this update address stakeholders’ concerns by amending the lease classification requirements for lessors to align them with practice under Topic 840 by requiring a lessor to classify a lease with variable payments as an operating lease on the commencement date of the lease if specified criteria are met. The amendments are effective for fiscal years beginning after December 15, 2021, for all entities, and interim periods within those fiscal years for public business entities with early application permitted. The Company adopted ASU 2021-05 during the third quarter of 2021. The adoption of this ASU did not have a material impact on the Company's Consolidated Financial Statements and related disclosures.

Certain Modifications or Exchanges of Freestanding Equity-Classified Written Call Options: In May 2021, the FASB issued ASU 2021-04, Earnings Per Share (Topic 260), Debt—Modifications and Extinguishments (Subtopic 470-50), Compensation—Stock Compensation (Topic 718), and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40) (“ASU 2021-04”). The amendments in this update provide final guidance that requires issuers to account for modifications or exchanges of freestanding equity-classified written call options, such as the Company’s outstanding Series A warrants, that remain equity classified after the modification or exchange based on the economic substance of the modification or exchange. This ASU addresses the diversity in practice in issuers’ accounting by providing a principles-based framework to determine whether an issuer should recognize the modification or exchange as 1) an adjustment to equity and, if so, the related earnings per share effects, if any, or 2) an expense and, if so, the manner and pattern of recognition. For all entities, the standard is effective for fiscal years beginning after December 15, 2021, with early adoption permitted. The Company adopted ASU 2021-04 during the second quarter of 2021. The adoption of this ASU did not have a material impact on the Company's Consolidated Financial Statements and related disclosures.

Reference Rate Reform: In January 2021, the FASB issued ASU 2021-01, Reference Rate Reform (Topic 848) (“ASU 2021-01”). The amendments in this update clarify that certain optional expedients and exceptions in Topic 848 for contract modifications and hedge accounting apply to derivatives that are affected by the discounting transition. For all entities, the standard is effective immediately. The Company adopted ASU 2021-01 during the first quarter of 2021. The adoption of this ASU did not have a material impact on the Company's Consolidated Financial Statements and related disclosures.

Convertible Debt and Contracts in Entity’s Own Equity: In August 2020, the FASB issued ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40) (“ASU 2020-06”). The amendments in this update simplify the accounting for certain financial instruments with characteristics of liabilities and equity, including convertible instruments and contracts in an entity’s own equity, such as the Company’s outstanding Series A warrants. For public business entities, the standard is effective for fiscal years beginning after December 15, 2021, with early adoption permitted. The Company adopted ASU 2020-06 during the first quarter of 2021. The adoption of this ASU did not have a material impact on the Company's Consolidated Financial Statements and related disclosures.

Credit Losses: In June 2016, the FASB issued ASU 2016-13, Credit Losses (“ASU 2016-13”). ASU 2016-13, along with related amendments and improvements issued in 2018 and 2019, replaces the previous incurred loss impairment methodology in U.S. GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable supportable information to inform credit loss estimates for financial instruments that are in the scope of this update, including trade accounts receivable. The Company adopted ASU 2016-13 during the first quarter of 2020. The adoption of this ASU did not have a material impact on the Company's Consolidated Financial Statements and related disclosures and resulted in a cumulative-effect adjustment to retained earnings of $440 in the Consolidated Balance Sheet as of January 1, 2020.

Recent Accounting Guidance Issued Not Yet Effective
Government Assistance: In November 2021, the FASB issued ASU 2021-10, Disclosures by Business Entities about Government Assistance (“ASU 2021-10”). This update requires business entities to make annual disclosures about transactions with a government accounted for by analogizing to a grant or contribution accounting model. The required annual disclosures include the nature of the transaction, the related accounting policy, the financial statement line items affected and the amounts reflected in the current period financial statements, and any significant terms and conditions. The amendments are effective for fiscal years beginning after December 15, 2021, for all entities, with early application permitted. The adoption of this ASU is not expected to have a material impact on the Company’s Consolidated Financial Statements and related disclosures.
v3.22.0.1
Discontinued Operations
 12 Months Ended
Dec. 31, 2021
Discontinued Operations and Disposal Groups [Abstract]  
Discontinued Operations Discontinued Operations
Discontinued operations consisted of activity related to the Company’s former NAPP operations.

Former NAPP Operations

On November 11, 2020, the Company entered into a unit purchase agreement (the “UPA”) to sell its thermal coal mining operations located in Pennsylvania consisting primarily of its Cumberland mining complex and related property (“Cumberland Transaction”) to a third party purchaser Iron Senergy Holdings, LLC (“Iron Senergy”). The Cumberland Transaction closed on December 10, 2020. In accordance with terms of the UPA, the Company transferred its equity interests in certain subsidiaries (Cumberland Contura, LLC, Contura Coal Resources, LLC, Contura Pennsylvania Land, LLC, Emerald Contura, LLC, and Contura Pennsylvania Terminal, LLC) along with total consideration of $49,987 to Iron Senergy. Pursuant to the terms of the UPA, the Company also retained certain assets and liabilities associated with its former NAPP operations. The mining permits associated with the Cumberland mining operations were obtained by Iron Senergy at closing. During the second quarter of 2021, nearly all of the Company’s remaining surety bonds were released and Iron Senergy’s replacement bonds were accepted through the administrative process with only $30 remaining as of December 31, 2021, which are expected to be released in the short-term.

The following table presents the details of the Cumberland Transaction:
Year Ended December 31, 2020
Cash$19,987 
Surety bonding collateral30,000 
Total consideration49,987 
Transaction costs2,205 
Carrying value of assets and liabilities (1)
$(16,079)
Loss on sale$36,113 
(1) Assets and liabilities were primarily comprised of property, plant and equipment, net of $32,872, deferred longwall move expenses of $15,173, and coal and supplies inventory of $5,112 and asset retirement obligations of $39,573, severance of $17,143, black lung obligations of $8,290, and subsidence liability of $3,559.

In connection with the UPA, the Company entered into certain agreements with Iron Senergy under which Iron Senergy will sell to the Company all of the coal that the Company is obligated to sell to customers under Cumberland coal supply agreements (“Cumberland CSAs”) which existed as of the transaction closing date but did not transfer to Iron Senergy at closing (each, a “Cumberland Back-to-Back Coal Supply Agreement”). Each Cumberland Back-to-Back Coal Supply Agreement has economic terms identical to, but offsetting, the related Cumberland CSA. If a Cumberland customer subsequently consents to assign a Cumberland CSA to Iron Senergy after closing, the related Cumberland CSA will immediately and automatically transfer to Iron Senergy and the related Cumberland Back-to-Back Coal Supply Agreements executed by the parties shall thereupon terminate as set forth therein. As the Company does not control the purchased coal prior to customer delivery, the Company will record coal purchases and sales under the related agreements on a net basis. Per terms of the Cumberland Back-to-Back Coal Supply Agreements, the Company is required to purchase and sell 2,014 tons of coal in 2022 totaling $77,844. For the years ended December 31, 2021 and 2020, the Company purchased and sold 2,591 and 104 tons, respectively, totaling $100,338 and $3,997, respectively, under the Cumberland Back-to-Back Coal Supply Agreements. The Cumberland Back-to-Back Coal Supply Agreements are scheduled to be fully performed by December 31, 2022.

Major Financial Statement Components of Discontinued Operations

The income from discontinued operations before income taxes for the year ended December 31, 2021 was $1,660. The major components of net loss from discontinued operations before income taxes in the Consolidated Statements of Operations for the year ended December 31, 2020 are as follows:
Year Ended December 31, 2020 (1)
Revenues:
Total revenues$235,509 
Costs and expenses:
Cost of coal sales (exclusive of items shown separately below)215,390 
Depreciation, depletion and amortization11,570 
Accretion on asset retirement obligations4,154 
Asset impairment and restructuring (2)
172,640 
Selling, general and administrative expenses (3)
1,623 
Other income(926)
Other non-major expense items, net374 
Loss on sale36,113 
Loss from discontinued operations before income taxes$(205,429)
(1) Includes minor residual activity related to the Company’s former PRB operations.
(2) Refer to Note 8.
(3) Represents professional and legal fees.

Refer to the Consolidated Statements of Operations and Note 6 for net income (loss) per share information related to discontinued operations.

The major components of assets and liabilities that are classified as discontinued operations in the Consolidated Balance Sheets are as follows:
December 31,
20212020
Assets:  
Trade accounts receivable, net of allowance for doubtful accounts$— $7,504 
Prepaid expenses and other current assets$462 $3,431 
Other non-current assets (1)
$8,526 $9,473 
Liabilities:  
Trade accounts payable, accrued expenses and other current liabilities$5,838 $12,306 
Workers’ compensation and black lung obligations, non-current$23,683 $27,799 
Other non-current liabilities$— $1,291 
(1) Primarily comprised of workers’ compensation insurance receivable and long-term restricted investments collateralizing workers’ compensation obligations.

The major components of cash flows related to discontinued operations were as follows:
Year Ended December 31,
2020
Depreciation, depletion and amortization$11,570 
Capital expenditures$34,411 
Other significant operating non-cash items related to discontinued operations:
Accretion on asset retirement obligations$4,154 
Asset impairment and restructuring$172,640 
v3.22.0.1
Revenue
 12 Months Ended
Dec. 31, 2021
Revenue from Contract with Customer [Abstract]  
Revenue Revenue
Disaggregation of Revenue from Contracts with Customers

ASC 606 requires that entities disclose disaggregated revenue information in categories (such as type of good or service, geography, market, type of contract, etc.) that depict how the nature, amount, timing, and uncertainty of revenue and cash flow are affected by economic factors. ASC 606 explains that the extent to which an entity’s revenue is disaggregated depends on the facts and circumstances that pertain to the entity’s contracts with customers and that some entities may need to use more than one type of category to meet the objective for disaggregating revenue.

The Company earns revenues primarily through the sale of coal produced at Company operations and coal purchased from third parties. The Company extracts, processes and markets met and thermal coal from deep and surface mines for sale to steel and coke producers, industrial customers, and electric utilities. The Company conducts mining operations only in the United States with mines in Central Appalachia. The Company has one reportable segment: Met. In addition to the one reportable segment, the All Other category includes general corporate overhead and corporate assets and liabilities, the former CAPP - Thermal operations, and the elimination of certain intercompany activity, as well as expenses associated with certain idled/closed mines. Refer to Note 24 for further segment information.

The Company has disaggregated revenue between met coal and thermal coal and export and domestic revenues which depicts the pricing and contract differences between the two. Export revenue generally is derived by spot or short term contracts with pricing determined at the time of shipment or based on a market index; whereas domestic revenue is characterized by contracts that typically have a term of one year or longer and typically the pricing is fixed. The following tables disaggregate the Company’s coal revenues by product category and by market to depict how the nature, amount, timing, and uncertainty of the Company’s coal revenues and cash flows are affected by economic factors:
Year Ended December 31, 2021
Met CoalThermal CoalTotal
Export coal revenues$1,675,147 $30,879 $1,706,026 
Domestic coal revenues396,160 150,411 546,571 
Total coal revenues$2,071,307 $181,290 $2,252,597 
Year Ended December 31, 2020
Met CoalThermal CoalTotal
Export coal revenues$870,121 $27,904 $898,025 
Domestic coal revenues362,654 152,445 515,099 
Total coal revenues$1,232,775 $180,349 $1,413,124 
Performance Obligations

The Company considers each individual transfer of coal on a per shipment basis to the customer a performance obligation. The pricing terms of the Company’s contracts with customers include fixed pricing, variable pricing, or a combination of both fixed and variable pricing. All the Company’s revenue derived from contracts with customers is recognized at a point in time. The following table includes estimated revenue expected to be recognized in the future related to performance obligations that are unsatisfied as of December 31, 2021.
20222023202420252026Total
Estimated coal revenues (1)
$65,768 $14,199 $— $— $— $79,967 
(1) Amounts only include estimated coal revenues associated with contracts with customers with fixed pricing with original expected duration of more than one year. The Company has elected not to disclose the aggregate amount of the transaction price allocated to the performance obligations that are unsatisfied (or partially unsatisfied) as of the end of the reporting period for performance obligations with either of the following conditions: 1) the remaining performance obligation is part of a contract that has an original expected duration of one year or less; or 2) the remaining performance obligation has variable consideration that is allocated entirely to a wholly unsatisfied performance obligation.
v3.22.0.1
Accumulated Other Comprehensive Loss
 12 Months Ended
Dec. 31, 2021
Equity [Abstract]  
Accumulated Other Comprehensive Loss Accumulated Other Comprehensive Loss
The following tables summarize the changes to accumulated other comprehensive loss during the years ended December 31, 2021 and 2020:
Balance January 1, 2021Other comprehensive income before reclassificationsAmounts reclassified from accumulated other comprehensive lossBalance December 31, 2021
Employee benefit costs$(111,985)$47,461 $6,021 $(58,503)
Balance January 1, 2020
Other comprehensive loss before reclassificationsAmounts reclassified from accumulated other comprehensive loss
Balance December 31, 2020
Employee benefit costs$(58,616)$(60,647)$7,278 $(111,985)

The following table summarizes the amounts reclassified from accumulated other comprehensive loss and the Consolidated Statements of Operations line items affected by the reclassification during the years ended December 31, 2021 and 2020:
Details about accumulated other comprehensive loss componentsAmounts reclassified from accumulated other comprehensive lossAffected line item in the Consolidated Statements of Operations
Year Ended December 31,
20212020
Employee benefit costs:
Amortization of actuarial loss (1)
$5,653 $3,929 
Miscellaneous income (loss), net
Settlement (1)
368 3,349 
Miscellaneous income (loss), net
Total before income tax$6,021 $7,278 
Income tax— — Income tax (expense) benefit
Total, net of income tax$6,021 $7,278 
(1) These accumulated other comprehensive loss components are included in the computation of net periodic benefit costs for certain employee benefit plans. Refer to Note 19.
v3.22.0.1
Net Income (Loss) per Share
 12 Months Ended
Dec. 31, 2021
Earnings Per Share [Abstract]  
Net Income (Loss) per Share Net Income (Loss) per Share
The number of shares used to calculate basic net income (loss) per common share is based on the weighted average number of the Company’s outstanding common shares during the respective period. The number of shares used to calculate diluted net income (loss) per common share is based on the number of common shares used to calculate basic net income (loss) per common share plus the dilutive effect of stock options and other stock-based instruments held by the Company’s employees and directors during the period, and the Company’s outstanding Series A warrants. The dilutive effect of outstanding stock-based instruments is determined by application of the treasury stock method. The warrants become dilutive for diluted net income (loss) per common share calculations when the market price of the Company’s common stock exceeds the exercise price. As discussed below, dilutive securities are not included in the computation of diluted net loss per common share for the year ended December 31, 2020 as the impact would be anti-dilutive.
For the years ended December 31, 2021 and 2020, 717,992 and 1,317,351 warrants, stock options, and other stock-based instruments, respectively, were excluded from the computation of dilutive net income (loss) per common share because they would have been anti-dilutive. When applying the treasury stock method, anti-dilution generally occurs when the exercise prices or unrecognized compensation cost per share are higher than the Company’s average stock price during an applicable period.

Anti-dilution also occurs in periods of a net loss, and the dilutive impact of all share-based compensation awards are excluded. For the year ended December 31, 2020, the weighted average share impact of stock options and other stock-based instruments that were excluded from the calculation of diluted shares due to the Company incurring a net loss for the period was 142,250.
The following table presents the net income (loss) per common share for the years ended December 31, 2021 and 2020:

Year Ended December 31,
20212020
Net income (loss)
Income (loss) from continuing operations$286,929 $(241,470)
Income (loss) from discontinued operations1,861 (205,429)
Net income (loss)$288,790 $(446,899)
Basic
Weighted average common shares outstanding - basic18,441,175 18,298,362 
Basic income (loss) per common share:
Income (loss) from continuing operations$15.56 $(13.20)
Income (loss) from discontinued operations0.10 (11.22)
Net income (loss)$15.66 $(24.42)
Diluted
Weighted average common shares outstanding - basic18,441,175 18,298,362 
Diluted effect of warrants35,574 — 
Diluted effect of stock options1,753 — 
Diluted effect of other stock-based instruments393,180 — 
Weighted average common shares outstanding - diluted18,871,682 18,298,362 
Diluted income (loss) per common share:
Income (loss) from continuing operations$15.20 $(13.20)
Income (loss) from discontinued operations0.10 (11.22)
Net income (loss)$15.30 $(24.42)
v3.22.0.1
Inventories, net
 12 Months Ended
Dec. 31, 2021
Inventory Disclosure [Abstract]  
Inventories, net Inventories, net
Inventories, net consisted of the following: 
December 31,
 20212020
Raw coal$20,347 $15,084 
Saleable coal81,240 69,262 
Materials, supplies and other, net (1)
27,795 23,705 
Total inventories, net$129,382 $108,051 
(1) Includes an increase in allowance for obsolete material and supplies inventory of $807 recorded as restructuring expense during the year ended December 31, 2020 (refer to Note 8).
v3.22.0.1
Asset Impairment and Restructuring
 12 Months Ended
Dec. 31, 2021
Restructuring and Related Activities [Abstract]  
Asset Impairment and Restructuring Asset Impairment and Restructuring
Long-lived Asset Impairment for the Year Ended December 31, 2021

During the year ended December 31, 2021, long-lived asset impairment of $60 was recorded in the All Other category to reduce the carrying value of property, plant, and equipment, net, due to capital spending during the period at previously impaired locations requiring the impairment of certain additional assets not considered recoverable.

Long-lived Asset Impairment for the Year Ended December 31, 2020

During the year ended December 31, 2020, weakening coal market conditions due in part to the impact of the global COVID-19 Pandemic, as well as the following events resulted in quarterly impairment testing:

•During the second quarter of 2020, the Company announced that it would take certain strategic actions with respect to two of its thermal coal mining complexes in an effort to strengthen its financial performance and improve forecasted liquidity. The Company announced that an underground mine and preparation plant located in West Virginia would be idled during the third quarter of 2020. In addition, the Company decided not to move forward with the construction of a new refuse impoundment at its Cumberland mine in Pennsylvania and would therefore no longer spend the significant capital required in connection with the project. As a result, the Cumberland mine was expected to cease production by the end of 2022. On December 10, 2020, the Company sold its Cumberland mining operations. Refer to Note 3 for further details.

•During the fourth quarter of 2020, changes in mine plans and the determination that certain mineral reserves previously forecasted to be mined were no longer considered economic due to poor geologic conditions reduced forecasted cash flows for one Met and one All Other asset group to amounts below those required for full recoverability.

The Company performed long-lived asset impairment tests as of November 30, 2020, August 31, 2020, May 31, 2020, and February 29, 2020. In total, the Company determined that indicators of impairment with respect to five long-lived asset groups within its Met reporting segment, three long-lived asset groups within its All Other category, and one long-lived asset group within discontinued operations existed during the year ended December 31, 2020.

The following tables present the details of the long-lived asset impairments during the year ended December 31, 2020:

Year Ended December 31, 2020
First QuarterSecond QuarterThird QuarterFourth QuarterYear Ended
Continuing operations:
Met
$32,951 $— $— $13,366 $46,317 
All Other758 17,390 219 16,270 34,637 
Total from continuing operations$33,709 $17,390 $219 $29,636 $80,954 
Discontinued operations:$— $144,348 $3,297 $— $147,645 
Total long-lived asset impairment:$33,709 $161,738 $3,516 $29,636 $228,599 
Year Ended December 31, 2020
First QuarterSecond QuarterThird QuarterFourth QuarterYear Ended
Continuing operations:
Mineral rights, net
$21,825 $2,241 $— $17,513 $41,579 
Property, plant, and equipment, net
6,066 6,496 219 5,450 18,231 
Acquired mine permits, net5,818 8,653 — 6,673 21,144 
Total from continuing operations$33,709 $17,390 $219 $29,636 $80,954 
Discontinued operations:
Mineral rights, net
$— $16,364 $— $— $16,364 
Property, plant, and equipment, net
— 127,984 3,297 — 131,281 
Total from discontinued operations$— $144,348 $3,297 $— $147,645 
Total long-lived asset impairment:
Mineral rights, net
$21,825 $18,605 $— $17,513 $57,943 
Property, plant, and equipment, net
6,066 134,480 3,516 5,450 149,512 
Acquired mine permits, net5,818 8,653 — 6,673 21,144 
Total long-lived asset impairment$33,709 $161,738 $3,516 $29,636 $228,599 

Restructuring

As a result of the strategic actions announced in the second quarter of 2020 and subsequent changes to severance and employee-related benefits, the Company recorded restructuring expense of ($621) in the All Other category during the year ended December 31, 2021.

As a result of the strategic actions discussed above, the Company recorded restructuring expense during the year ended December 31, 2020 as follows:
Year Ended December 31, 2020
Total Restructuring
Continuing Operations (3)
Discontinued Operations
Severance and employee-related benefits (1)
$26,037 $2,117 $23,920 
Other costs (2)
1,882 807 1,075 
Total restructuring expense$27,919 $2,924 $24,995 

(1) Severance and employee-related benefits were considered probable and estimable based on provisions of contractual agreements and existing employee benefit plans.
(2) Includes accelerated amortization of deferred longwall move expenses of $668, allowance for advanced mining royalties of $407, and allowance for obsolete materials and supplies inventory of $807.
(3) Total restructuring expense from continuing operations of $2,924 was recorded within the All Other category and affected Accrued expenses and other current liabilities, Other non-current liabilities, Inventories, net, and Other non-current assets.
v3.22.0.1
Prepaid Expenses and Other Current Assets
 12 Months Ended
Dec. 31, 2021
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]  
Prepaid Expense and Other Current Assets Prepaid Expenses and Other Current Assets
Prepaid expenses and other current assets consisted of the following:
December 31,
 20212020
Prepaid freight$19,671 $8,515 
Notes and other receivables4,161 13,245 
Short-term restricted cash11,977 9,311 
Prepaid insurance8,525 6,510 
Refundable income taxes— 64,565 
Prepaid bond premium1,649 2,576 
Other prepaid expenses1,707 1,530 
Total prepaid expenses and other current assets$47,690 $106,252 
v3.22.0.1
Property, Plant, and Equipment, Net
 12 Months Ended
Dec. 31, 2021
Property, Plant and Equipment [Abstract]  
Property, Plant, and Equipment, Net Property, Plant, and Equipment, net
Property, plant, and equipment, net, consisted of the following: 
December 31,
 20212020
Plant and mining equipment$642,874 $603,463 
Mine development115,357 96,008 
Land26,389 26,606 
Office equipment, software and other1,462 1,379 
Construction in progress19,992 18,587 
Total property, equipment and mine development costs$806,074 $746,043 
Less accumulated depreciation, depletion and amortization(443,856)(382,423)
Total property, plant, and equipment, net$362,218 $363,620 
Included in plant and mining equipment are assets under financing leases totaling $8,611 and $7,907 with accumulated depreciation of $5,624 and $3,645 as of December 31, 2021 and December 31, 2020, respectively.
Depreciation and amortization expense associated with property, plant, equipment, and non-mineral asset retirement obligation assets, net, was $86,506 and $153,631 for the years ended December 31, 2021 and 2020, respectively.

Depreciation expense for the years ended December 31, 2021 and 2020 includes a credit of ($307) and ($3,689), respectively, related to revisions to asset retirement obligations. Refer to Note 16 for further disclosures related to asset retirement obligations.

During the years ended December 31, 2021 and 2020, the Company recorded long-lived asset impairments which reduced the carrying value of property, plant, and equipment, net, by $60 and $18,231, respectively. Refer to Note 8 for further information.
As of December 31, 2021, the Company had commitments to purchase approximately $18,497 of new equipment, expected to be acquired at various dates in 2022.
v3.22.0.1
Other Non-Current Assets
 12 Months Ended
Dec. 31, 2021
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]  
Other Non-Current Assets Other Non-Current Assets
Other non-current assets consisted of the following:
December 31,
 20212020
Advanced mining royalties$10,788 $13,132 
Long-term deposits1,371 28,200 
Long-term restricted investments28,443 23,768 
Equity method investments20,460 18,383 
Workers’ compensation receivables45,335 48,320 
Other24,660 17,579 
Total other non-current assets$131,057 $149,382 
v3.22.0.1
Leases
 12 Months Ended
Dec. 31, 2021
Leases [Abstract]  
Leases Leases
The Company’s lease population consists primarily of vehicle and heavy equipment leases and leases for office equipment. The Company’s building and land leases relate to corporate office space and certain site offices. The Company determines whether a contract contains a lease based on whether the Company obtains the right to control the use of specifically identifiable property, plant, and equipment for a period of time in exchange for consideration. For the years ended December 31, 2021 and 2020, the Company identified no instances requiring significant judgment in determining whether any contracts entered into during the period were or were not leases. Additionally, the Company had no material sublease agreements within the scope of ASC 842 or lease agreements for which the Company was the lessor for the years ended December 31, 2021 and 2020.

Renewal options in the Company’s lease population primarily relate to month-to-month extensions on vehicle leases and are immaterial both individually and in the aggregate. The Company includes renewal options that are reasonably certain to be exercised in the measurement of lease liabilities. As of December 31, 2021, the Company does not intend to exercise any termination options on existing leases.

As of December 31, 2021 and 2020, the Company had the following right-of-use assets and lease liabilities within the Company’s Consolidated Balance Sheets:
December 31, 2021December 31, 2020
AssetsBalance Sheet Classification
Financing lease assetsProperty, plant, and equipment, net$2,987 $4,262 
Operating lease right-of-use assetsOther non-current assets5,003 5,671 
Total lease assets$7,990 $9,933 
LiabilitiesBalance Sheet Classification
Financing lease liabilities - currentCurrent portion of long-term debt$1,878 $2,014 
Operating lease liabilities - currentAccrued expenses and other current liabilities547 595 
Financing lease liabilities - long-termLong-term debt791 1,996 
Operating lease liabilities - long-termOther non-current liabilities4,456 5,076 
Total lease liabilities$7,672 $9,681 

Total lease costs and other lease information for the years ended December 31, 2021 and 2020 included the following:
Year Ended December 31, 2021Year Ended December 31, 2020
Lease cost (1)
Financing lease cost:
     Amortization of leased assets$2,061 $3,238 
     Interest on lease liabilities245 358 
Operating lease cost1,383 2,105 
Short-term lease cost786 1,518 
     Total lease cost$4,475 $7,219 
(1) The Company had no variable lease costs or sublease income for the years ended December 31, 2021 and 2020.

Year Ended December 31,
20212020
Other information
Cash paid for amounts included in the measurement of lease liabilities$4,478 $7,157 
     Operating cash flows from financing leases$245 $358 
     Operating cash flows from operating leases$2,169 $3,623 
     Financing cash flows from financing leases$2,064 $3,176 
Right-of-use assets obtained in exchange for new financing lease liabilities$703 $221 
Right-of-use assets obtained in exchange for new operating lease liabilities$275 $(12)
Lease Term and Discount Rate
Weighted-average remaining lease term in years - financing leases1.751.94
Weighted-average remaining lease term in years - operating leases7.888.45
Weighted-average discount rate - financing leases9.6 %6.1 %
Weighted-average discount rate - operating leases11.3 %11.5 %

The Company has elected to show net instead of gross amounts for right-of-use assets and liabilities within its Consolidated Statements of Cash Flows.

The following table summarizes the maturity of the Company’s lease liabilities on an undiscounted cash flow basis and a reconciliation to the lease liabilities recognized in the Company’s Consolidated Balance Sheets as of December 31, 2021:
Financing LeasesOperating Leases
Lease cost
2022$2,072 $1,100 
2023522 1,066 
2024259 955 
2025150 897 
20263 884 
Thereafter— 2,775 
Total future minimum lease payments$3,006 $7,677 
Imputed interest(337)(2,674)
Present value of future minimum lease payments$2,669 $5,003 
As of December 31, 2021, the Company had no leases with future commencement dates that will create significant rights or obligations for the Company.
Leases Leases
The Company’s lease population consists primarily of vehicle and heavy equipment leases and leases for office equipment. The Company’s building and land leases relate to corporate office space and certain site offices. The Company determines whether a contract contains a lease based on whether the Company obtains the right to control the use of specifically identifiable property, plant, and equipment for a period of time in exchange for consideration. For the years ended December 31, 2021 and 2020, the Company identified no instances requiring significant judgment in determining whether any contracts entered into during the period were or were not leases. Additionally, the Company had no material sublease agreements within the scope of ASC 842 or lease agreements for which the Company was the lessor for the years ended December 31, 2021 and 2020.

Renewal options in the Company’s lease population primarily relate to month-to-month extensions on vehicle leases and are immaterial both individually and in the aggregate. The Company includes renewal options that are reasonably certain to be exercised in the measurement of lease liabilities. As of December 31, 2021, the Company does not intend to exercise any termination options on existing leases.

As of December 31, 2021 and 2020, the Company had the following right-of-use assets and lease liabilities within the Company’s Consolidated Balance Sheets:
December 31, 2021December 31, 2020
AssetsBalance Sheet Classification
Financing lease assetsProperty, plant, and equipment, net$2,987 $4,262 
Operating lease right-of-use assetsOther non-current assets5,003 5,671 
Total lease assets$7,990 $9,933 
LiabilitiesBalance Sheet Classification
Financing lease liabilities - currentCurrent portion of long-term debt$1,878 $2,014 
Operating lease liabilities - currentAccrued expenses and other current liabilities547 595 
Financing lease liabilities - long-termLong-term debt791 1,996 
Operating lease liabilities - long-termOther non-current liabilities4,456 5,076 
Total lease liabilities$7,672 $9,681 

Total lease costs and other lease information for the years ended December 31, 2021 and 2020 included the following:
Year Ended December 31, 2021Year Ended December 31, 2020
Lease cost (1)
Financing lease cost:
     Amortization of leased assets$2,061 $3,238 
     Interest on lease liabilities245 358 
Operating lease cost1,383 2,105 
Short-term lease cost786 1,518 
     Total lease cost$4,475 $7,219 
(1) The Company had no variable lease costs or sublease income for the years ended December 31, 2021 and 2020.

Year Ended December 31,
20212020
Other information
Cash paid for amounts included in the measurement of lease liabilities$4,478 $7,157 
     Operating cash flows from financing leases$245 $358 
     Operating cash flows from operating leases$2,169 $3,623 
     Financing cash flows from financing leases$2,064 $3,176 
Right-of-use assets obtained in exchange for new financing lease liabilities$703 $221 
Right-of-use assets obtained in exchange for new operating lease liabilities$275 $(12)
Lease Term and Discount Rate
Weighted-average remaining lease term in years - financing leases1.751.94
Weighted-average remaining lease term in years - operating leases7.888.45
Weighted-average discount rate - financing leases9.6 %6.1 %
Weighted-average discount rate - operating leases11.3 %11.5 %

The Company has elected to show net instead of gross amounts for right-of-use assets and liabilities within its Consolidated Statements of Cash Flows.

The following table summarizes the maturity of the Company’s lease liabilities on an undiscounted cash flow basis and a reconciliation to the lease liabilities recognized in the Company’s Consolidated Balance Sheets as of December 31, 2021:
Financing LeasesOperating Leases
Lease cost
2022$2,072 $1,100 
2023522 1,066 
2024259 955 
2025150 897 
20263 884 
Thereafter— 2,775 
Total future minimum lease payments$3,006 $7,677 
Imputed interest(337)(2,674)
Present value of future minimum lease payments$2,669 $5,003 
As of December 31, 2021, the Company had no leases with future commencement dates that will create significant rights or obligations for the Company.
v3.22.0.1
Accrued Expenses and Other Current Liabilities
 12 Months Ended
Dec. 31, 2021
Payables and Accruals [Abstract]  
Accrued Expenses and Other Current Liabilities Accrued Expenses and Other Current Liabilities
Accrued expenses and other current liabilities consisted of the following: 
December 31,
 20212020
Wages and benefits$52,310 $40,330 
Workers’ compensation 10,582 10,355 
Black lung 7,235 6,784 
Taxes other than income taxes30,734 21,540 
Current portion of asset retirement obligations32,159 24,990 
Accrued interest and fees14,489 15,902 
Deferred revenue— 13,197 
Freight accrual15,085 2,610 
Other 12,013 4,698 
Total accrued expenses and other current liabilities$174,607 $140,406 
v3.22.0.1
Long-Term Debt
 12 Months Ended
Dec. 31, 2021
Debt Disclosure [Abstract]  
Long-Term Debt Long-Term Debt
Long-term debt consisted of the following: 
December 31,
 20212020
Term Loan Credit Facility - due June 2024$449,435 $553,373 
ABL Facility - due December 2024— 3,350 
LCC Note Payable— 27,500 
LCC Water Treatment Obligation— 6,875 
Other (1)
5,311 8,475 
Debt discount and issuance costs(6,195)(17,046)
Total long-term debt $448,551 $582,527 
Less current portion(2,989)(28,830)
Long-term debt, net of current portion$445,562 $553,697 
(1) Includes financing leases, refer to Note 12 for additional information.

Term Loan Credit Facility - due June 2024

On June 14, 2019, the Company entered into a Credit Agreement with Cantor Fitzgerald Securities, as administrative agent and collateral agent, and the other lenders party thereto (as defined therein) that provides for a senior secured term loan facility in the aggregate principal amount of $561,800 with a maturity date of June 14, 2024 (the “Term Loan Credit Facility”). Principal repayments equal to approximately $1,405 were due each March, June, September and December (commencing with September 30, 2019) with the final principal repayment installment to be paid on the maturity date and in an amount equal to the aggregate principal amount outstanding on such date. The Term Loan Credit Facility bears an interest rate per annum based on the character of the loan (defined as either “Base Rate Loan” or “Eurocurrency Rate Loan”). Each loan type bears interest at a rate per annum comprised of a base rate (as defined) plus an applicable percentage (6.00% for Base Rate Loans and 7.00% for Eurocurrency Rate Loans on or prior to the second anniversary of the Closing Date and 7.00% or 8.00% thereafter (the “Applicable Rate”)). The Eurocurrency base rate is subject to a 2.00% floor. Interest accrued on each Base Rate Loan is payable in arrears on the last business day of each March, June, September and December and the maturity date. Interest accrued on each Eurocurrency Rate Loan is payable in arrears on the last day of each interest period as defined therein. As of December 31, 2021, the borrowings made under the Term Loan Credit Facility were comprised of Eurocurrency Rate Loans with an interest rate of 10.00%, calculated as the Eurocurrency rate during the period plus an applicable rate of 8.00%. As of December 31, 2021, the carrying value of the Term Loan Credit Facility was $443,241, all of which was classified as long-term within the
Consolidated Balance Sheets. As of December 31, 2020, the carrying value of the Term Loan Credit Facility was $540,643, with $5,618 classified as current, within the Consolidated Balance Sheets.

During the three months ending September 30, 2021, the Company repurchased and permanently retired, through privately negotiated transactions, $18,724 of outstanding principal borrowings under the Term Loan Credit Facility. These borrowings were repurchased at a discount resulting in an aggregate purchase price of $18,415. As the participating lenders were existing shareholders (related parties) of the Company as of the repurchase date, the Company analyzed various factors regarding each of the transactions and concluded such repurchases were at a reasonable market rate and reflected the terms of an arm’s length transaction per the requirements of the Term Loan Credit Facility. Additionally, on December 31, 2021 and September 30, 2021, the Company made voluntary prepayments of $50,000 and $31,000, respectively, of outstanding principal borrowings under the Term Loan Credit Facility. As a result of the prepayments, no further amortization payments under the Term Loan Credit Facility are required prior to maturity.

All obligations under the Term Loan Credit Facility are guaranteed by substantially all of Alpha’s direct and indirect subsidiaries. Certain obligations under the Term Loan Facility are secured by a senior lien, subject to certain exceptions (including the ABL Priority Collateral described below), by substantially all of Alpha’s assets and the assets of Alpha’s subsidiary guarantors (“Term Loan Priority Collateral”), in each case subject to exceptions. The obligations under the Term Loan Credit Facility are also secured by a junior lien, again subject to certain exceptions, against the ABL Priority Collateral. The Term Loan Facility contains negative and affirmative covenants including certain financial covenants that are more flexible than the covenants on the Second Amended and Restated Credit Agreement dated December 6, 2021. The Company was in compliance with all covenants under this agreement as of December 31, 2021.

Second Amended and Restated Asset-Based Revolving Credit Agreement

On December 6, 2021, the Company entered into the Second Amended and Restated Asset-Based Revolving Credit Agreement with Citibank N.A as administrative agent, collateral agent, swingline lender, and L/C issuer and the other lenders party thereto (the “Lenders”), and BMO Harris Bank N.A and Eclipse Business Capital LLC as co-collateral agents. The Second Amended and Restated Asset-Based Revolving Credit Agreement (“New ABL Agreement”) amended and restated the Amended and Restated Asset-Based Revolving Credit Agreement dated November 9, 2018, in its entirety, and includes a senior secured asset-based revolving credit facility (“the New ABL Facility”). Under the New ABL Facility, the Company may borrow cash from the Lenders (as defined therein) or cause the L/C Issuers (as defined therein) to issue letters of credit, on a revolving basis, in an aggregate amount of up to $155,000, of which no more than $150,000 may represent outstanding letters of credit ($125,000 on a committed basis and another $25,000 on an uncommitted cash collateralized basis) with a maturity date of December 6, 2024. The New ABL Agreement extended the maturity date of the facility from the previous maturity of April 3, 2022. Under the terms of the New ABL Agreement, letters of credit fees will be calculated at 5.25%, while any future borrowings will bear interest based on the character of the loan (defined as either secured overnight financing rate “SOFR” Loan (“SOFR Loan”) or “Base Rate Loan”) plus an applicable rate of 4.50% for SOFR Loans and 3.50% for Base Rate Loans. Pursuant to terms of the New ABL Agreement at each notice period, the Company elects the character of the loan, the interest period, and may provide notice of continuation or conversion of the borrowed principal amount with the ability to repay the borrowed principal amount in advance of the maturity date without penalty. As of the date of the refinance and as of December 31, 2021, no borrowings were outstanding under the New ABL Facility.

The New ABL Agreement provides that a specified percentage of billed and unbilled receivables and raw and clean inventory meeting certain criteria are eligible to be counted for purposes of collateralizing the amount of financing available, subject to certain terms and conditions. Availability under the New ABL Facility is calculated on a monthly basis and fluctuates based on qualifying amounts of coal inventory and trade accounts receivable (the “Borrowing Base”) and the facility's covenant limitations related to the Fixed Charge Coverage Ratio (as defined in therein). In accordance with terms of the New ABL Facility, the Company may be required to collateralize the New ABL Facility to the extent outstanding borrowings and letters of credit under the New ABL Facility exceed the Borrowing Base after considering covenant limitations.

Any letter of credit issued under the New ABL Facility will bear a commitment fee rate of 0.50%, and a fronting fee of 0.25% of the face amount under each letter of credit. As of December 31, 2021, the Company had $121,037 letters of credit outstanding under the New ABL Facility.
The New ABL Facility is guaranteed by substantially all of Alpha’s direct and indirect subsidiaries (together with Alpha, the “Loan Parties”) and secured by all or substantially all assets of the Loan Parties, including equity in Alpha’s direct domestic subsidiaries, as collateral for the obligations under the New ABL Facility. The New ABL Facility has a first lien on ABL priority collateral and a second lien on Term Loan Priority Collateral. The New ABL Agreement, as amended, and related documents contain negative and affirmative covenants including certain financial covenants. The Company is in compliance with all covenants under these agreements as of December 31, 2021.

Amended and Restated Asset-Based Revolving Credit Agreement

On November 9, 2018, the Company entered into the Amended and Restated Asset-Based Revolving Credit Agreement with Citibank N.A. as administrative agent, collateral agent, and swingline lender and the other lenders party thereto (the “Lenders”), and Citibank N.A., Barclays Bank PLC, BMO Harris Bank N.A. and Credit Suisse AG as letter of credit issuers (“LC Lenders”). The Amended and Restated Asset-Based Revolving Credit Agreement amended and restated the Asset-Based Revolving Credit Agreement dated April 3, 2017, in its entirety, and included a senior secured asset-based revolving credit facility (the “ABL Facility”). Under the ABL Facility, the Company could borrow cash from the Lenders (as defined therein) or cause the L/C Issuers (as defined therein) to issue letters of credit, on a revolving basis, in an aggregate amount of up to $225,000, of which no more than $200,000 could be drawn through letters of credit. Any borrowings under the ABL Facility had a maturity date of April 3, 2022 and incurred interest based on the character of the loan (defined as either “Base Rate Loan” or “Eurocurrency Rate Loan”) plus an applicable rate ranging from 1.00% to 1.50% for Base Rate Loans and 2.00% to 2.50% for Eurocurrency Rate Loans, depending on the amount of credit available. Pursuant to terms of the Amended and Restated Asset-Based Revolving Credit Agreement at each notice period, the Company elected the character of the loan, the interest period, and could provide notice of continuation or conversion of the borrowed principal amount with the ability to repay the borrowed principal amount in advance of the maturity date without penalty. On March 20, 2020, the Company borrowed $57,500 principal amount under the ABL Facility. The funds were borrowed to augment the Company’s short-term operational flexibility in the face of uncertainty created by the spread of the COVID-19 virus and its potential effects. As of December 6, 2021, the date the Company entered into the New ABL Agreement, there were no outstanding borrowings under the ABL Facility. As of December 31, 2020, the carrying value of the ABL Facility was $3,350, all of which was classified as long-term within the Consolidated Balance Sheets, with the outstanding borrowings comprised of Eurocurrency Rate Loans with an interest rate of 2.73%, calculated as the Eurocurrency rate during the period plus an applicable rate of 2.50%.

The Amended and Restated Asset-Based Revolving Credit Agreement provided that a specified percentage of billed, unbilled and approved foreign receivables and raw and clean inventory meeting certain criteria were eligible to be counted for purposes of collateralizing the amount of financing available, subject to certain terms and conditions. Availability under the ABL Facility was calculated on a monthly basis and fluctuated based on qualifying amounts of coal inventory and trade accounts receivable (the “Borrowing Base”) and the facility's covenant limitations related to the Fixed Charge Coverage Ratio (as defined in therein). In accordance with terms of the ABL Facility, the Company was required to collateralize the ABL Facility to the extent outstanding borrowings and letters of credit under the ABL Facility exceeded the Borrowing Base after considering covenant limitations. Due to fluctuations of the Borrowing Base, the Company was required to post $25,000 of collateral in January 2021 to remain in compliance with the terms of the ABL Facility as of December 31, 2020. During the first quarter of 2021, a portion of the posted cash collateral was used to repay the remaining $3,350 in borrowings under the ABL Facility, and the remaining posted cash collateral was returned to unrestricted cash.

Any letters of credit issued under the ABL Facility incurred a commitment fee rate ranging from 0.25% to 0.375% depending on the amount of availability per terms of the agreement, and a fronting fee of 0.25% of the face amount under each letter of credit, payable to the ABL Facility’s administrative agent. As of December 31, 2020, the Company had $123,108 letters of credit outstanding under the ABL Facility.

LCC Note Payable

As a result of the Merger, the Company assumed a note payable to Lexington Coal Company (“LCC”) in the aggregate amount of $62,500 (the “LCC Note Payable”) and with a maturity date of July 26, 2022. The LCC Note Payable had no stated interest rate and an imputed interest rate of 12.45%. Principal repayments of $17,500 were due each July during 2019, 2020 and 2021, with the final principal payment of $10,000 due on the maturity date. On July 26, 2021, the Company prepaid $7,700 of the final principal payment. As a result of the prepayment, $13,982 of surety collateral was returned. In October 2021, the Company elected to repay in full the remaining $2,300 of the final principal payment.
There was no remaining carrying value of the LCC Note Payable as of December 31, 2021. As of December 31, 2020, the carrying value of the LCC Note Payable was $24,423, with $17,500 reported within the current portion of long-term debt.

LCC Water Treatment Stipulation

As a result of the Merger, the Company assumed an obligation to contribute $12,500 into LCC’s water treatment restricted cash accounts (the “LCC Water Treatment Stipulation”). Contributions equal to $625 were due each January, April, July and October from 2019 through 2023. The LCC Water Treatment Stipulation had no stated interest rate and an imputed interest rate of 13.12%. In October 2021, the Company elected to repay in full the remaining $5,000 obligation.

There was no remaining carrying value of the LCC Water Treatment Stipulation as of December 31, 2021. As of December 21, 2020, the carrying value of the LCC Water Treatment Stipulation was $5,636, with $1,875 reported within the current portion of long-term debt.

Future Maturities

Future maturities of long-term debt as of December 31, 2021 are as follows: 
2022$2,989 
20231,367 
2024450,245 
2025142 
20263 
Total long-term debt$454,746 
v3.22.0.1
Acquisition-Related Obligations
 12 Months Ended
Dec. 31, 2021
Fair Value Disclosures [Abstract]  
Acquisition-Related Obligations Acquisition-Related Obligations
Acquisition-related obligations consisted of the following:
December 31,
20212020
Contingent Revenue Obligation$35,005 $28,967 
Environmental Settlement Obligations6,633 10,391 
UMWA Funds Settlement Liability— 2,000 
Discount(233)(1,491)
Total acquisition-related obligations $41,405 $39,867 
Less current portion(22,405)(19,099)
Acquisition-related obligations, net of current portion$19,000 $20,768 

The Company entered into various settlement agreements with Alpha Natural Resources, Inc. and/or the Alpha Natural Resources, Inc. bankruptcy successor ANR, Inc. and third parties as part of the Alpha Natural Resources, Inc. bankruptcy reorganization process. The Company assumed acquisition-related obligations through those settlement agreements which became effective on July 26, 2016, the effective date of Alpha Natural Resources, Inc.’s plan of reorganization. Additionally, as a result of the Merger, the Company assumed certain acquisition-related obligations pursuant to the terms stipulated within the bankruptcy settlement previously entered into by the Merger Companies.

Contingent Revenue Obligation

As a result of the Merger, the Company assumed a contingent revenue payment obligation (the “Contingent Revenue Obligation”) to certain of the Merger Companies’ creditors pursuant to the terms stipulated within the bankruptcy settlement previously entered into by the Merger Companies. Pursuant to terms of the obligation, the annual obligation will be limited to revenues derived from legacy operations for the Merger Companies and will not include revenues related to legacy Alpha Metallurgical Resources, Inc. operations. The Contingent Revenue Obligation consists of a contingent revenue payment of
1.5% of annual gross revenues of the legacy operations for the Merger Companies up to $500,000 and 1.0% of annual gross revenue of the legacy operations for the Merger Companies in excess of $500,000 through the period ended December 31, 2022. As of December 31, 2021 and 2020, the carrying value of the Contingent Revenue Obligation was $35,005 and $28,967, with $16,005 and $11,393 classified as current, respectively, and classified as an acquisition-related obligation in the Consolidated Balance Sheets. Refer to Note 17 for further disclosures related to the fair value assignment and methods used.

Refer to Note 21 for disclosures related to a Contingent Revenue Obligation repurchase transaction with a related party during the fourth quarter of 2021. Additionally, during the second quarter of 2021, the Company paid $11,396 pursuant to terms of the Contingent Revenue Obligation. During the second quarter of 2020, the Company paid $15,084, including $374 of unclaimed unsecured claims distributions, pursuant to terms of the Contingent Revenue Obligation.

Environmental Settlement Obligations

As a result of the Merger, the Company assumed certain environmental settlement obligations (the “Environmental Settlement Obligations”) pursuant to the terms stipulated within the bankruptcy settlement previously entered into by the Merger Companies. These obligations include payments to a third-party environmental agency and the funding of certain reclamation related projects through 2022. As of December 31, 2021 and 2020, the carrying value of the Environmental Settlement Obligations was $6,400 and $9,237, net of discounts of $233 and $1,154, with $6,400 and $6,044 classified as current, respectively, all of which was classified as an acquisition-related obligation in the Consolidated Balance Sheets.
v3.22.0.1
Asset Retirement Obligations
 12 Months Ended
Dec. 31, 2021
Asset Retirement Obligation Disclosure [Abstract]  
Asset Retirement Obligations Asset Retirement Obligations
The following table summarizes the changes in asset retirement obligations for the years ended December 31, 2021 and 2020:
Total asset retirement obligations at December 31, 2019$203,137 
Accretion for the period 26,504 
Sites added during the period621 
Revisions in estimated cash flows (1)
(43,765)
Expenditures for the period(21,433)
Total asset retirement obligations at December 31, 2020$165,064 
Accretion for the period26,520 
Sites added during the period 2,125 
Revisions in estimated cash flows (1)
(12,744)
Expenditures for the period(16,793)
Total asset retirement obligations at December 31, 2021$164,172 
Less current portion (2)
(32,159)
Long-term portion$132,013 
(1)    The revisions in estimated cash flows resulted primarily from discount rate adjustments and changes in mine plans.
(2)    Included within Accrued expenses and other current liabilities on the Company’s Consolidated Balance Sheets. Refer to Note 13.
v3.22.0.1
Fair Value of Financial Instruments and Fair Value Measurements
 12 Months Ended
Dec. 31, 2021
Fair Value Disclosures [Abstract]  
Fair Value of Financial Instruments and Fair Value Measurements Fair Value of Financial Instruments and Fair Value Measurements
The estimated fair values of financial instruments are determined based on relevant market information. These estimates involve uncertainty and cannot be determined with precision.
The carrying amounts for cash and cash equivalents, trade accounts receivable, net, prepaid expenses and other current assets, short-term and long-term restricted cash, short-term and long-term deposits, trade accounts payable, and accrued expenses and other current liabilities approximate fair value as of December 31, 2021 and 2020 due to the short maturity of these instruments.
The following tables set forth by level, within the fair value hierarchy, the Company’s long-term debt at fair value as of December 31, 2021 and 2020:
December 31, 2021
Carrying
     Amount (1)
Total Fair
Value		Quoted Prices in Active Markets (Level 1)Significant Other Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Term Loan Credit Facility - due June 2024$443,241 $447,561 $— $447,561 $— 
Total long-term debt$443,241 $447,561 $— $447,561 $— 

December 31, 2020
Carrying
Amount (1)
Total Fair
Value		Quoted Prices in Active Markets (Level 1)Significant Other Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Term Loan Credit Facility - due June 2024$540,643 $379,614 $— $379,614 $— 
ABL Facility - due April 2022 (2)
3,350 3,057 — — 3,057 
LCC Note Payable24,423 20,328 — — 20,328 
LCC Water Treatment Obligation5,636 4,281 — — 4,281 
Total long-term debt$574,052 $407,280 $— $379,614 $27,666 
(1) Net of debt discounts and debt issuance costs.
(2) On December 6, 2021, the Company entered into a New ABL Agreement. Refer to Note 14 for additional information.

The following tables set forth by level, within the fair value hierarchy, the Company’s acquisition-related obligations at fair value as of December 31, 2021 and 2020:
 December 31, 2021
Carrying
Amount (1)
Total Fair ValueQuoted Prices in Active Markets (Level 1)Significant Other Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Environmental Settlement Obligations$6,400 $6,270 $— $— $6,270 
Total acquisition-related obligations$6,400 $6,270 $— $— $6,270 

 December 31, 2020
Carrying
Amount (1)
Total Fair ValueQuoted Prices in Active Markets (Level 1)Significant Other Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
UMWA Funds Settlement Liability$1,662 $1,426 $— $— $1,426 
Environmental Settlement Obligations9,237 7,760 — — 7,760 
Total acquisition-related obligations$10,899 $9,186 $— $— $9,186 
(1) Net of discounts.

The following table sets forth by level, within the fair value hierarchy, the Company’s financial and non-financial assets and liabilities that were accounted for at fair value on a recurring basis as of December 31, 2021 and 2020. Financial and non-financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement requires judgment, and may affect the determination of fair value for assets and liabilities and their placement within the fair value hierarchy levels.
 December 31, 2021
Total Fair ValueQuoted Prices in Active Markets (Level 1)Significant Other Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Contingent Revenue Obligation$35,005 $— $— $35,005 
Trading securities$28,443 $27,075 $1,368 $— 
 December 31, 2020
Total Fair ValueQuoted Prices in Active Markets (Level 1)Significant Other Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Contingent Revenue Obligation$28,967 $— $— $28,967 
Trading securities$22,498 $20,092 $2,406 $— 

The following table is a reconciliation of the financial and non-financial assets and liabilities that were accounted for at fair value on a recurring basis and that were categorized within Level 3 of the fair value hierarchy:
December 31, 2020PaymentsLoss Recognized in EarningsTransfer In (Out) of Level 3 Fair Value HierarchyDecember 31, 2021
Contingent Revenue Obligation $28,967 $(13,487)$19,525 $— $35,005 
(1) The loss recognized in earnings resulted primarily from an increase in forecasted future revenue as of December 31, 2021.

December 31, 2019PaymentsGain Recognized in EarningsTransfer In (Out) of Level 3 Fair Value HierarchyDecember 31, 2020
Contingent Revenue Obligation$52,427 $(14,710)$(8,750)$— $28,967 
(1) The gain recognized in earnings resulted primarily from a change in the forecasted future revenue associated with this obligation and an increase in annualized volatility as of December 31, 2020.

The following methods and assumptions were used to estimate the fair values of the assets and liabilities in the tables above:
Level 1 Fair Value Measurements
Trading Securities - Includes money market funds and other cash equivalents. The fair value is based on observable market data.

Level 2 Fair Value Measurements
Term Loan Credit Facility - due June 2024 - The fair value is based on the average between bid and ask prices provided by a third-party. As the fair value is based on observable market inputs and due to limited trading volume in the Term Loan Credit Facility, the Company has classified the fair value within Level 2 of the fair value hierarchy.

Trading Securities - Includes certificates of deposit, mutual funds, corporate debt securities and U.S. treasury and agency securities. The fair values of the Company’s trading securities are obtained from a third-party pricing service provider. The fair values provided by the pricing service provider are based on observable market inputs including credit spreads and broker-dealer quotes, among other inputs. The Company classifies the prices obtained from the pricing services within Level 2 of the fair value hierarchy because the underlying inputs are directly observable from active markets. However, the pricing models used entail a certain amount of subjectivity and therefore differing judgments in how the underlying inputs are modeled could result in different estimates of fair value.

Level 3 Fair Value Measurements
ABL Facility - due April 2022 - Observable transactions are not available to aid in determining the fair value of this item. Therefore, the fair value was derived by using the expected present value approach in which estimated cash flows are discounted using a risk-free interest rate adjusted for credit risk (discount rate of approximately 9% as of December 31, 2020). On December 6, 2021, the Company entered into a New ABL Agreement. Refer to Note 14 for additional information.

LCC Note Payable, LCC Water Treatment Obligation, UMWA Funds Settlement Liability and Environmental Settlement Obligations - Observable transactions are not available to aid in determining the fair value of these items. Therefore, the fair value was derived by using the expected present value approach in which estimated cash flows are discounted using a risk-free interest rate adjusted for credit risk (discount rates of approximately 13% and 34% as of December 31, 2021 and 2020, respectively).

Contingent Revenue Obligation - The fair value of the Contingent Revenue Obligation was estimated using a Black-Scholes pricing model and is marked to market at each reporting period with changes in value reflected in earnings. The inputs included in the Black-Scholes pricing model are the Company's forecasted future revenue, the stated royalty rate, the remaining periods in the obligation, annual risk-free interest rate based on the U.S. Constant Maturity Treasury Curve and annualized volatility. The annualized volatility was calculated by observing volatilities for comparable companies with adjustments for the Company's size and leverage. The range of significant unobservable inputs used to value the Contingent Revenue Obligation as of December 31, 2021 and 2020 are set forth in the following table:
 December 31, 2021December 31, 2020
Forecasted future revenue
$1.5 - $2.0 billion
$0.9 - $1.1 billion
Stated royalty rate
1.0% - 1.5%
1.0% - 1.5%
Annualized volatility
18.4% - 39.3% (29.9%)
19.4% - 52.1% (28.0%)
v3.22.0.1
Income Taxes
 12 Months Ended
Dec. 31, 2021
Income Tax Disclosure [Abstract]  
Income Taxes Income Taxes
Total income tax expense (benefit) provided on income (loss) before income taxes was allocated as follows:
Year Ended December 31,
20212020
Continuing operations$3,609 $(2,164)
Discontinued operations(201)— 
Total$3,408 $(2,164)

Significant components of income tax expense (benefit) from continuing operations were as follows:
Year Ended December 31,
20212020
Current tax expense (benefit):
Federal$2,586 $(35,187)
State1,186 (99)
Total current$3,772 $(35,286)
Deferred tax (benefit) expense:
Federal$(3)$33,348 
State(160)(226)
Total deferred $(163)$33,122 
Total income tax expense (benefit):
Federal$2,583 $(1,839)
State1,026 (325)
Total$3,609 $(2,164)

A reconciliation of statutory federal income tax expense (benefit) on income (loss) from continuing operations to the actual income tax expense (benefit) is as follows:
Year Ended December 31,
20212020
Federal statutory income tax expense (benefit)$61,013 $(51,163)
Increase (reductions) in taxes due to:
Percentage depletion allowance(11,864)(2,039)
AMT sequestration refund— (2,123)
State taxes, net of federal tax impact12,998 (9,640)
State apportioned tax rate change, net of federal tax impact8,751 (1,235)
Change in valuation allowances(78,056)59,929 
Capital loss expiration10,552 — 
Stock-based compensation405 1,739 
Other, net (190)2,368 
Income tax expense (benefit)$3,609 $(2,164)

Deferred income taxes result from temporary differences between the reporting of amounts for financial statement purposes and income tax purposes. The net deferred tax assets and liabilities included in the Consolidated Balance Sheets include the following amounts:
Year Ended December 31,
20212020
Deferred tax assets:
  Asset retirement obligations$36,252 $41,268 
  Reserves and accruals not currently deductible9,610 12,131 
  Workers’ compensation benefit obligations47,105 59,478 
Pension obligations34,956 52,598 
  Equity method investments1,846 2,050 
Loss carryforwards, net of Section 382 limitation187,341 255,772 
  Acquisition-related obligations9,156 10,002 
  Other 7,100 10,976 
     Gross deferred tax assets333,366 444,275 
Less valuation allowance(172,883)(263,387)
     Deferred tax assets$160,483 $180,888 
Deferred tax liabilities:
Property, plant and mineral reserves$(134,075)$(141,549)
  Acquired intangibles, net(16,408)(22,037)
  Prepaid expenses(4,955)(6,211)
Restricted cash(5,362)(11,516)
  Other — (55)
     Total deferred tax liabilities(160,800)(181,368)
     Net deferred tax liabilities$(317)$(480)

Changes in the valuation allowance were as follows:
Year Ended December 31,
20212020
Valuation allowance beginning of period$263,387 $133,020 
(Decrease) increase in valuation allowance recorded to income tax expense (benefit) (78,043)117,829 
(Decrease) increase in valuation allowance not affecting income tax expense (benefit)(12,461)12,538 
Valuation allowance end of period$172,883 $263,387 

On December 22, 2017, President Trump signed into law legislation commonly referred to as the “Tax Cuts and Jobs Act” (“TCJA”). Among other provisions, the TCJA repealed the corporate alternative minimum tax (“AMT”) and provided a mechanism for corporations to monetize their alternative minimum tax credits (“AMT Credits”) as a refundable credit during the 2018 through 2021 tax years. On March 27, 2020, President Trump signed into law legislation referred to as the CARES Act. The CARES Act modified the AMT Credits provision such that a corporate taxpayer’s remaining AMT Credits would be refunded in the 2019 tax year rather than the 2019 through 2021 tax years. As of December 31, 2019, the Company recorded a current federal income tax receivable of $33,065 and a deferred tax asset of $33,065 in relation to its refundable AMT Credits. During the first quarter of 2020 and following enactment of the CARES Act, the Company reclassified the $33,065 deferred tax asset to a current federal income tax receivable. The Company received the $66,130 AMT Credit refund in the fourth quarter of 2020. In addition, the Company received $2,123 related to AMT Credits claimed in prior tax years under a different Internal Revenue Code section, which were previously and erroneously subjected to the budgetary sequestration provisions. The Company does not expect to receive any further benefits related to AMT Credits.

The Company acquired the core assets of Alpha Natural Resources, Inc. as part of the Alpha Natural Resources, Inc. bankruptcy reorganization in transactions intended to be treated as a tax-free reorganization for U.S. federal income tax purposes. As a result of these transactions, the Company inherited the tax basis of the core assets and the net operating loss and
other carryforwards of Alpha Natural Resources, Inc. On December 31, 2016, the net operating loss carryforwards and other carryforwards were reduced under Internal Revenue Code Section 108 due to the cancellation of indebtedness resulting from the Alpha Natural Resources, Inc. bankruptcy reorganization. Due to the change in ownership, the net operating loss and other carryforwards inherited in the Alpha Natural Resources, Inc. bankruptcy reorganization are subjected to significant limitations on their use in future years.

Due to the Company’s formation through acquisition of certain core coal assets as part of the Alpha Natural Resources, Inc. bankruptcy reorganization, the Company does not have a long history of operating results. Additionally, significant ownership change limitations limit the ability of the Company to utilize its net operating loss and other carryforwards in future years. The Company currently is relying primarily on the reversal of taxable temporary differences, along with consideration of taxable income via carryback to prior years and tax planning strategies, to support the realization of deferred tax assets. The Company assesses the realizability of its deferred tax assets, including scheduling the reversal of its deferred tax liabilities, to determine the amount of valuation allowance needed. Scheduling the reversal of deferred tax asset and liability balances requires judgment and estimation. The Company believes the deferred tax liabilities relied upon as future taxable income in its assessment will reverse in the same period and jurisdiction and are of the same character as temporary differences giving rise to the deferred tax assets that will be realized. The valuation allowance recorded represents the portion of deferred tax assets for which the Company is unable to support realization through the methods described above. The Company has concluded that it is more likely than not that the remaining deferred tax assets, net of valuation allowances, are realizable.

At December 31, 2021, the Company has regular tax net operating loss carryforwards for federal income tax purposes of approximately $1,543,000. This includes $1,008,000 that are available to offset regular federal taxable income subject to an annual Internal Revenue Code Section 382 limitation of approximately $1,000 and $270,000 that are subject to an annual Section 382 limitation of approximately $17,500. These federal net operating loss carryforwards were generated before 2018 and will expire between years 2030 and 2037. The Company also has $265,000 of federal net operating loss carryforwards with an indefinite carryforward period that can be used to offset up to 80% of taxable income. The Company has capital loss carryforwards of approximately $223,000. The capital loss carryforwards will expire between years 2022 and 2025. A full valuation allowance is recorded against the capital loss carryforwards.

During the third quarter of the year ended December 31, 2020, the Company recorded a decrease in unrecognized tax benefits of approximately $20,788 as a result of the issuance of final regulatory guidance from the Internal Revenue Service (“IRS”). The decrease in unrecognized tax benefits did not impact the Company’s effective tax rate for the year ended December 31, 2020.

The Company’s policy is to classify interest and penalties related to uncertain tax positions as part of income tax expense. As of December 31, 2021 and 2020, the Company had no accrued interest and penalties.

The following reconciliation illustrates the Company’s liability for uncertain tax positions:
Year Ended December 31,
20212020
Unrecognized tax benefits - beginning of period$— $20,788 
Reductions for tax positions of prior years— (20,788)
Unrecognized tax benefits - end of period$— $— 

As of December 31, 2021, tax years 2018 – 2021 remain open to federal and state examination. During the third quarter of 2021, the IRS concluded its audit of the Company’s 2016 federal income tax return and associated net operating loss (“NOL”) carryback claim. The audit conclusion did not result in any material impact to the financial statements or related disclosures. Following the conclusion of the audit, the Company received the $64,160 carryback claim tax refund and $5,425 of accrued interest.
v3.22.0.1
Employee Benefit Plans
 12 Months Ended
Dec. 31, 2021
Compensation Related Costs [Abstract]  
Employee Benefit Plans Employee Benefit Plans The Company provides several types of benefits for its employees, including defined benefit and defined contribution pension plans, workers’ compensation and black lung benefits, and postretirement life insurance. The Company does not participate in any multi-employer plans. The components of net periodic benefit (credit) cost other than the service cost
component for black lung and postretirement life insurance benefits are included in the line item miscellaneous income (loss), net, in the Consolidated Statements of Operations.

Company Administered Defined Benefit Pension Plans

In connection with the Merger, the Company assumed three qualified non-contributory defined benefit pension plans, which cover certain salaried and non-union hourly employees. The qualified non-contributory defined benefit pension plans are collectively referred to as the “Pension Plans.” Benefits are frozen under these plans. Participants accrued benefits either based on certain formulas, the participant’s compensation prior to retirement, or plan specified amounts for each year of service with the Company. One of the Company’s frozen qualified non-contributory defined benefit pension plans utilizes a cash balance formula for certain of its participants. The cash balance formula provides guaranteed rates of interest on accumulated balances of 6% for balances accumulated prior to 2004 and 4% on balances accumulated thereafter.

Annual funding contributions to the Pension Plans are made as recommended by consulting actuaries based upon the ERISA funding standards. Plan assets consist of equity securities, fixed income funds, commingled short-term funds, private equity funds, and a guaranteed insurance contract.

Effective in 2019, two of the qualified non-contributory defined benefit pension plans were amended to offer certain eligible participants the option to elect to receive lump sum benefits, which resulted in a partial plan settlement and the accelerated recognition of a portion of the accumulated other comprehensive loss during the years ended December 31, 2021 and December 31, 2020. Refer to the disclosures below for further information on the partial plan settlements.

The following tables set forth the Pension Plans’ accumulated benefit obligations, fair value of plan assets and funded status for the years ended December 31, 2021 and 2020.
Year Ended December 31,
20212020
Change in benefit obligations:
Accumulated benefit obligation at beginning of period:$723,448 $674,439 
Interest cost 13,566 18,730 
Actuarial (gain) loss (1)
(34,922)72,822 
Benefits paid(30,222)(30,916)
Settlement(3,815)(11,627)
Accumulated benefit obligation at end of period$668,055 $723,448 
Change in fair value of plan assets:
Fair value of plan assets at beginning of period$504,777 $470,353 
Actual return on plan assets30,814 54,222 
Employer contributions6,571 22,745 
Benefits paid(30,222)(30,916)
Settlement(3,815)(11,627)
Fair value of plan assets at end of period$508,125 $504,777 
Funded status$(159,930)$(218,671)
Accrued benefit cost at end of period (2)
$(159,930)$(218,671)
(1) For the years ended December 31, 2021 and 2020, the actuarial (gain) loss was primarily attributable to the change in the weighted-average discount rate actuarial assumption used in determining the benefit obligations.
(2) Amounts are classified as long-term on the Consolidated Balance Sheets as there are sufficient plan assets to make expected benefit payments to plan participants in the succeeding twelve months.

Gross amounts related to benefit obligations recognized in accumulated other comprehensive loss consisted of the following as of December 31, 2021 and 2020:
December 31,
20212020
Net actuarial loss$47,950 $88,583 

The following table details the components of net periodic benefit credit:
Year Ended December 31,
20212020
Interest cost$13,566 $18,730 
Expected return on plan assets(28,732)(27,064)
Amortization of net actuarial loss3,217 2,012 
Settlement412 1,636 
Net periodic benefit credit$(11,537)$(4,686)

Other changes in plan assets and benefit obligations recognized in other comprehensive income (loss) are as follows:
Year Ended December 31,
20212020
Actuarial (gain) loss$(37,004)$45,663 
Amortization of net actuarial loss(3,217)(2,012)
Settlement(412)(1,636)
Total recognized in other comprehensive income (loss)$(40,633)$42,015 

The following table presents information applicable to plans with accumulated benefit obligations in excess of plan assets:
Year Ended December 31,
20212020
Projected benefit obligation$668,055 $723,448 
Accumulated benefit obligation$668,055 $723,448 
Fair value of plan assets$508,125 $504,777 

The weighted-average actuarial assumption used in determining the benefit obligations as of December 31, 2021 and 2020 was as follows: 
December 31,
20212020
Discount rate2.92 %2.62 %

The weighted-average actuarial assumptions used to determine net periodic benefit credit for the years ended December 31, 2021 and 2020 were as follows: 
Year Ended December 31,
20212020
Discount rate for benefit obligation2.62 %3.35 %
Discount rate for interest cost1.96 %2.92 %
Expected long-term rate of return on plan assets5.80 %5.90 %

The discount rate assumptions were determined from a high-quality corporate bond yield-curve timing of the Company’s projected cash out flows.
The expected long-term rate of return on assets of the Pension Plans is established each year by the Company’s Benefits Committee in consultation with the plans’ actuaries and outside investment advisors. This rate is determined by taking into consideration the Pension Plans’ target asset allocation, expected long-term rates of return on each major asset class by reference to long-term historic ranges, inflation assumptions, and the expected additional value from active management of the Pension Plans’ assets. For the determination of net periodic benefit cost in 2022, the Company will utilize an expected long-term rate of return on plan assets of 5.80%.

Assets of the Pension Plans are held in trusts and are invested in accordance with investment guidelines that have been established by the Company’s Benefits Committee in consultation with outside investment advisors. The target allocation for 2022 and the actual asset allocation as reported at December 31, 2021 are as follows:
Target Allocation Percentages 2022 (1)
Percentage of Plan Assets 2021
Equity securities60.0 %56.0 %
Fixed income funds40.0 %41.0 %
Other— %3.0 %
Total100.0 %100.0 %
(1) Assumes the Pension Plans have a funded status level less than 90.0%.

The asset allocation targets have been set with the expectation that the Pension Plans’ assets will fund the expected liabilities within an appropriate level of risk. In determining the appropriate target asset allocations, the Benefits Committee considers the demographics of the Pension Plans’ participants, the funded status of each plan, the Company’s contribution philosophy, the Company’s business and financial profile, and other associated risk factors. The Pension Plans’ assets are periodically rebalanced among the major asset categories to maintain the asset allocation within a specified range of the target allocation percentage. The target allocation between equity securities and fixed income funds is determined by reference to the funded status percentage for each of the Pension Plans. The plan administrator uses a de-risking glide path whereby the fixed income funds allocation increases as the funded status improves. At a 90.0% funded status level, the glide path calls for a 50/50 equity securities and fixed income funds mix. During the year ended December 31, 2021, one of the Pension Plans funded status levels reached 90.0% and the related plan assets were adjusted accordingly to the new allocation. In September 2020, the target allocation was adjusted by the Company’s Benefits Committee to transition to 60.0% equity securities and 40.0% fixed income funds in approximate 2.0% increments over a 10-month period.

As a result of the recent funding relief granted under the American Rescue Plan Act, estimated contributions requirements to the pension plans were reduced relative to the Company’s previous estimates. The Company contributed $6,571 to the pension plans during the year ended December 31, 2021. The Company’s minimum required contributions are estimated to be $4,404 to the Pension Plans in 2022.

The following represents expected future pension benefit payments for the next ten years:
2022$30,949 
202330,944 
202431,161 
202531,497 
202631,657 
2027-2031158,207 
$314,415 

The fair values of the Company’s Pension Plans’ assets as of December 31, 2021, by asset category are as follows:
Asset CategoryTotalQuoted Market Prices in Active Market for Identical Assets (Level 1)Significant Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Equity securities:
Multi-asset fund (1)
$284,568 $— $284,568 $— 
Fixed income funds:
Bond fund (2)
208,466 — 208,466 — 
Commingled short-term fund (3)
1,384 — 1,384 — 
Other types of investments:
Guaranteed insurance contract11,652 — — 11,652 
Total$506,070 $— $494,418 $11,652 
Receivable (4)
876 
Total assets at fair value506,946 
Private equity funds measured at net asset value practical expedient (5)
1,179 
Total plan assets$508,125 
(1) This fund contains equities (domestic and international), real estate and bonds.
(2) This fund contains bonds representing a diversity of sectors and maturities. This fund also includes mortgage-backed securities and U.S. Treasuries.
(3) This fund contains cash and highly liquid short-term investments in a collective investment fund.
(4) Receivable for investments sold at December 31, 2021, which approximates fair value.
(5) In accordance with Accounting Standards Update 2015-07, investments that are measured at fair value using the net asset value per share practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the total value of assets of the plans.

Changes in Level 3 plan assets for the period ended December 31, 2021 were as follows:
Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
Guaranteed Insurance Contract
Beginning balance, December 31, 2020$11,454 
Actual return on plan assets:
Relating to assets still held at the reporting date528 
Purchases, sales and settlements(330)
Ending balance, December 31, 2021$11,652 

The fair values of the Company’s Pension Plans’ assets as of December 31, 2020, by asset category are as follows:
Asset CategoryTotalQuoted Market Prices in Active Market for Identical Assets (Level 1)Significant Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Equity securities:
Multi-asset fund (1)
$236,405 $— $236,405 $— 
Fixed income funds:
Bond fund (2)
253,218 — 253,218 — 
Commingled short-term fund (3)
1,405 — 1,405 — 
Other types of investments:
Guaranteed insurance contract11,454 — — 11,454 
Total$502,482 $— $491,028 $11,454 
Receivable (4)
888 
Total assets at fair value503,370 
Private equity funds measured at net asset value practical expedient (5)
1,407 
Total plan assets$504,777 
(1) This fund contains equities (domestic and international), real estate and bonds.
(2) This fund contains bonds representing a diversity of sectors and maturities. This fund also includes mortgage-backed securities and U.S. Treasuries.
(3) This fund contains cash and highly liquid short-term investments in a collective investment fund.
(4) Receivable for investments sold at December 31, 2020, which approximates fair value.
(5) In accordance with Accounting Standards Update 2015-07, investments that are measured at fair value using the net asset value per share practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the total value of assets of the plans.

Changes in Level 3 plan assets for the period ended December 31, 2020 were as follows:
Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
Guaranteed Insurance Contract
Beginning balance, December 31, 2019$11,155 
Actual return on plan assets:
Relating to assets still held at the reporting date659 
Purchases, sales and settlements(360)
Ending balance, December 31, 2020$11,454 

The following is a description of the valuation methodologies used for assets measured at fair value:

Level 1 Plan Assets: Assets consist of individual security positions that are easily traded on recognized market exchanges. These securities are priced and traded daily, and therefore the fund is valued daily.

Level 2 Plan Assets: Funds consist of individual security positions that are mostly securities easily traded on recognized market exchanges. These securities are priced and traded daily, and therefore the fund is valued daily.

Level 3 Plan Assets: Assets are valued monthly or quarterly based on the Market Value provided by managers of the underlying fund investments. The Market Value provided typically reflects the fair value of each underlying fund investment, including unrealized gains and losses.

Workers’ Compensation and Pneumoconiosis (Black Lung)
The Company is required by federal and state statutes to provide benefits to employees for awards related to workers’ compensation and black lung.

The Company’s subsidiaries utilize high-deductible third-party insurance for worker’s compensation and black lung obligations with the exception of certain subsidiaries in which the Company is a qualified self-insurer for workers’ compensation and/or black lung obligations. The Company’s subsidiaries that are self-insured for black lung benefits may fund benefit payments through a Section 501(c) (21) tax-exempt trust fund.

Pursuant to the Merger Agreement, the Company assumed a reinsurance contract with a third party. In 2017, the Merger Companies made a lump sum payment in exchange for a reinsurance company’s agreement to administer and pay certain future workers’ compensation and state black lung obligations in the state of Kentucky. Pursuant to the Merger Agreement, the Company assumed the estimated liability for these future claims. As the liabilities are paid by the insurance company, the prepaid insurance amounts will be reduced by a corresponding amount.

The Company accrues for workers’ compensation liability by recognizing costs when it is probable that a covered liability has been incurred and the cost can be reasonably estimated. The Company’s estimates of these costs are adjusted based upon actuarial studies and include a provision for incurred but not reported losses. Actual losses may differ from these estimates, which could increase or decrease the Company’s costs. Additionally, the liability for black lung benefits is estimated by an independent actuary by prorating the accrual of actuarially projected benefits over the employee’s applicable term of service. Adjustments to the probable ultimate liability for workers’ compensation and black lung are made annually based on actuarial valuations.

For the Company’s subsidiaries that are insured with a high-deductible insurance plan for workers’ compensation and black lung claims, the insurance premium expense for the years ended December 31, 2021 and 2020 was $8,602 and $7,000, respectively.

Workers’ Compensation

The table below presents workers’ compensation amounts recognized in the Consolidated Balance Sheets:
December 31,
20212020
Current liabilities$10,582 $10,355 
Current liabilities - discontinued operations (1)
2,730 4,847 
Long-term liabilities103,574 113,904 
Long-term liabilities - discontinued operations (1)
21,119 26,000 
Total liabilities$138,005 $155,106 
Less expected insurance receivable (2)
(47,644)(50,688)
Less long-term expected insurance receivable - discontinued operations (1)
(6,020)(6,970)
Workers’ compensation obligations, net of expected insurance receivables$84,341 $97,448 
(1) The discontinued operations consisted of activity related to the Company’s former NAPP operations. Refer to Note 3.
(2) Included within Prepaid expenses and other current assets and Other non-current assets in the Consolidated Balance Sheets.
Workers’ compensation expense for high-deductible insurance plans for the years ended December 31, 2021 and 2020 was $3,750 and $1,275, respectively.
Black Lung

The divestiture of the Company’s former NAPP operations during the fourth quarter of 2020 (refer to Note 3) resulted in a partial plan settlement of $8,290 and the accelerated recognition of a portion of the accumulated other comprehensive loss of $1,563 during the three months ended December 31, 2020. Refer to the disclosures below for further information on the partial plan settlement.

As a result of the strategic actions impacting certain mines during the three months ended June 30, 2020 (refer to Note 8), black lung obligations were revalued for curtailment and remeasured with an updated discount rate as of May 31, 2020, which resulted in an increase in the liability for black lung obligations of approximately $7,400 with the offset to accumulated other comprehensive loss and a slight increase in net periodic expense to be recognized subsequent to the remeasurement date. Refer to the disclosures below for further information.

The following tables set forth the accumulated black lung benefit obligations, fair value of plan assets and funded status for the years ended December 31, 2021 and 2020:
Year Ended December 31,
20212020
Change in benefit obligation:
Accumulated benefit obligation at beginning of period$127,506 $122,788 
Service cost2,972 2,361 
Interest cost2,463 3,240 
Actuarial (gain) loss (1)
(9,759)14,736 
Benefits paid(6,040)(7,166)
Curtailment gain— (163)
Settlement— (8,290)
Accumulated benefit obligation at end of period$117,142 $127,506 
Change in fair value of plan assets:
Fair value of plan assets at beginning of period$2,720 $2,660 
Actual return on plan assets(56)60 
Benefits paid(6,040)(7,166)
Employer contributions6,040 7,166 
Fair value of plan assets at end of period (2)
2,664 2,720 
Funded status$(114,478)$(124,786)
Accrued benefit cost at end of period$(114,478)$(124,786)
Summary of accrued benefit cost at end of period:
Continuing operations(111,854)(122,961)
Discontinued operations (3)
(2,624)(1,825)
Total accrued benefit cost at end of period$(114,478)$(124,786)
(1) For the years ended December 31, 2021 and 2020, the actuarial (gain) loss was primarily attributable to the change in the weighted-average discount rate actuarial assumption used in determining the benefit obligations.
(2) Assets of the plan are held in a Section 501(c)(21) tax-exempt trust fund and consist primarily of government debt securities. All assets are classified as Level 1 and valued based on quoted market prices.
(3) The discontinued operations consisted of activity related to the Company’s former NAPP operations. Refer to Note 3.

The table below presents amounts recognized in the Consolidated Balance Sheets:
December 31,
20212020
Current liabilities$7,235 $6,784 
Current liabilities - discontinued operations60 26 
Long-term liabilities104,619 116,177 
Long-term liabilities - discontinued operations2,564 1,799 
Total liabilities$114,478 $124,786 

Gross amounts related to the black lung benefit obligations recognized in accumulated other comprehensive loss consisted of the following as of December 31, 2021 and 2020: 
December 31,
20212020
Net actuarial loss $11,940 $24,042 

The following table details the components of the net periodic benefit cost for the black lung benefit obligations:
Year Ended December 31,
20212020
Service cost$2,972 $2,361 
Interest cost2,463 3,240 
Expected return on plan assets(54)(54)
Amortization of net actuarial loss 2,453 1,942 
Settlement— 1,563 
Net periodic benefit cost$7,834 $9,052 
Summary net periodic benefit cost:
Continuing operations$7,418 $7,670 
Discontinued operations (1)
416 1,382 
Total net periodic benefit cost$7,834 $9,052 
(1) The discontinued operations consisted of activity related to the Company’s former NAPP operations. Refer to Note 3.

Other changes in the black lung plan assets and benefit obligations recognized in other comprehensive income (loss) are as follows:
Year Ended December 31,
20212020
Actuarial (gain) loss$(9,649)$14,567 
Amortization of net actuarial loss(2,453)(1,942)
Settlement— (1,563)
Total recognized in other comprehensive income (loss)$(12,102)$11,062 

The weighted-average assumptions related to black lung obligations used to determine the benefit obligation as of December 31, 2021 and 2020 were as follows: 
December 31,
20212020
Discount rate2.96 %2.75 %
Federal black lung income benefit trend rate2.00 %2.00 %
Federal black lung medical benefit trend rate5.00 %5.00 %
Black lung benefit expense inflation rate (1)
— %2.00 %
(1) Effective in 2021, the annual claim administration expenses are incorporated into the annual service cost component of the net periodic benefit cost for the black lung benefit obligations.

The weighted-average assumptions related to black lung benefit obligations used to determine net periodic benefit cost were as follows:
Year Ended December 31,
20212020
Discount rate for benefit obligation2.75 %3.47 %
Discount rate for service cost3.15 %3.56 %
Discount rate for interest cost1.96 %2.61 %
Federal black lung income benefit trend rate2.00 %2.50 %
Federal black lung medical benefit trend rate5.00 %5.00 %
Black lung benefit expense inflation rate (1)
— %2.00 %
Expected return on plan assets2.00 %2.00 %
(1) Effective in 2021, the annual claim administration expenses are incorporated into the annual service cost component of the net periodic benefit cost for the black lung benefit obligations.

Estimated future cash payments related to black lung benefit obligations for the next 10 years ending after December 31, 2021 are as follows: 
Year ending December 31:
2022$7,295 
20237,208 
20247,254 
20257,329 
20267,497 
2027-203119,889 
$56,472 

Postretirement Life Insurance Benefits

As part of the Alpha Natural Resources, Inc. bankruptcy reorganization process and the Retiree Committee Settlement Agreement, the Company assumed the unfunded liability for life insurance benefits for certain disabled and non-union retired employees. Provisions are made for estimated benefits and adjustments to the probable ultimate liabilities are made annually based on an actuarial study prepared by independent actuaries. As of December 31, 2021 and 2020, the postretirement life insurance benefit obligation was $11,610, including a current portion $602, and $12,635, including a current portion $628, respectively, which are included in the Consolidated Balance Sheets as Other non-current liabilities and Accrued expenses and other current liabilities.

Defined Contribution and Profit-Sharing Plans

The Company sponsors defined contribution plans to assist its eligible employees in providing for retirement. Generally, under the terms of these plans, employees make voluntary contributions through payroll deductions and the Company makes
matching and/or discretionary contributions, as defined by each plan. The Company’s total contributions to these plans for the years ended December 31, 2021 and 2020 were $10,276 and $3,613, respectively.

During the second quarter of 2020, the Company’s matching contributions under the Alpha Metallurgical Resources (formerly Contura Energy) 401(k) Retirement Savings Plan (the “Plan”) were suspended due to weak market conditions at that time. Effective in June 2021, the Company’s matching contributions under the Plan were reinstated.

Self-insured Medical Plan
The Company is self-insured for health benefit coverage for all of its active employees. Estimated liabilities for health and medical claims are recorded based on the Company’s historical experience and include a component for incurred but not paid claims. During the years ended December 31, 2021 and 2020, the Company incurred total expenses of $63,127 and $52,517, respectively, which primarily include claims processed and an estimate for claims incurred but not paid.
v3.22.0.1
Stock-Based Compensation Awards
 12 Months Ended
Dec. 31, 2021
Share-based Payment Arrangement [Abstract]  
Stock-Based Compensation Awards Stock-Based Compensation Awards
The MIP is currently authorized for the issuance of awards of up to 1,201,202 shares of common stock, and as of December 31, 2021, there were 37,805 shares of common stock available for grant under the MIP. The Long-Term Incentive Plan (the “LTIP”) is currently authorized for the issuance of awards of up to 1,500,000 shares of common stock, and as of December 31, 2021, there were 870,503 shares of common stock available for grant under the LTIP. Pursuant to the Merger Agreement, the Company assumed the ANR Inc. 2017 Equity Incentive Plan (the “ANR EIP”), which had underlying ANR shares that were converted to 89,766 Contura Energy, Inc. shares. The ANR EIP is not authorized for additional issuance of awards of shares of common stock, and as of December 31, 2021, there were no shares of common stock available for grant under the ANR EIP.
As of December 31, 2021, the Company had four types of stock-based awards outstanding: time-based restricted stock units, performance-based restricted stock units, stock options, and performance-based cash awards. Stock-based compensation expense totaled $7,468 and $5,540 for the years ended December 31, 2021 and 2020, respectively. For the years ended December 31, 2021 and 2020, approximately 89% and 83%, respectively, of stock-based compensation expense was reported as selling, general and administrative expenses, and the remainder was recorded as cost of coal sales.
The Company is authorized to repurchase common shares from employees (upon the election by the employee) to satisfy the employees’ statutory tax withholdings upon the vesting of stock grants. Shares that are repurchased to satisfy the employees’ statutory tax withholdings are recorded in treasury stock at cost. During the year ended December 31, 2021, the Company repurchased 50,363 shares of its common stock issued pursuant to awards under the MIP and LTIP for a total purchase amount of $785, or $15.60 average price paid per share. During the year ended December 31, 2020, the Company repurchased 43,559 shares of its common stock issued pursuant to awards under the MIP, LTIP and ANR EIP for a total purchase amount of $209, or $4.79 average price paid per share.
2021 Awards Granted
During the year ended December 31, 2021, the Company granted certain key employees and non-employee directors 223,496 time-based restricted stock units under the MIP and LTIP with a weighted average grant date fair value of $12.03 based on the Company’s closing stock price at the trading day before the date of the grant. The awards granted to key employees will vest ratably over a three-year period from date of grant in accordance with the vesting schedule, subject to the participant’s continuous service with the Company through each applicable vesting date. The restricted stock units granted to non-employee directors on February 10, 2021 will vest on the first to occur of (i) April 30, 2021, (ii) the director’s separation from service due to the director’s death or physical or mental incapacity to perform his or her usual duties, such condition likely to remain continuously and permanently, as determined by the Company, and (iii) a change in control. The restricted stock units granted to non-employee directors on May 1, 2021 will vest on the first to occur of (i) April 30, 2022, (ii) the director’s service as a member of the board of directors is terminated, for any reason other than removal for cause, as of a date that is more than six months after the date of grant, and (iii) a change in control. Upon vesting and settlement of time-based restricted stock units, the Company issues authorized and unissued shares of the Company’s common stock to the recipient.
Additionally, during the year ended December 31, 2021, the Company granted certain key employees 167,587 performance-based restricted stock units granted under the LTIP which represent the number of shares of common stock that may be issued based on the achievement of targeted performance levels related to pre-established relative total shareholder
return goals and annually determined operational goals over a three year period. These awards are scheduled to cliff vest on the third anniversary of the date of the grant, subject to the participant’s continuous service with the Company through the applicable vesting date and the satisfaction of the performance criteria. These performance-based restricted stock units have the potential to be earned from 0% to 200% of target depending on actual results. Upon vesting and settlement of these awards, the Company will issue authorized and previously unissued shares of the Company’s common stock to the recipient. The 100,552 operational performance-based restricted stock units were valued based on the Company’s closing stock price at the trading day before the date of the grant and had a weighted average grant date fair value of $12.00. For the awards with operational performance conditions, the Company reassesses at each reporting date whether achievement of each of the performance conditions was probable and adjusts the accrual of stock-based compensation expense as needed. The 67,035 relative total shareholder return performance-based restricted stock units were valued relative to the stock price performance of a comparator group and had a weighted average grant date fair value of $16.18 based on a Monte Carlo simulation. The Monte Carlo simulation incorporated the assumptions as presented in the following table:
Relative performance-based restricted stock units
Start price (1)
$11.81 
Valuation date stock price (2)
$11.34 
Expected volatility (3)
98.54 %
Risk-free interest rate (4)
0.18 %
Expected dividend yield (5)
— %
(1)    The start price for the Company represented the average closing stock price over the twenty trading days ending on December 31, 2020, assuming dividends distributed during this period were reinvested in additional shares of the Company’s stock on the ex-dividend date.
(2)    The valuation date stock price represented the closing price on the grant date.
(3)    The expected volatility assumption was based on the historical volatility of the price of the Company’s stock.
(4)    The annual risk-free interest rate equaled the yield on the semi-annual zero coupon U.S. Treasury rates converted to continuously compounded rates that had a term equal to the length of the remaining performance measurement period as of the valuation date.
(5)    The expected dividend yield represented the investments return to a share of the Company’s stock that is not available to the holder of the performance-based restricted stock unit.

Additionally, the Company granted certain key employees performance-based cash incentive awards granted under the LTIP with a target award amount of $927. The cash to be awarded is based on the achievement of pre-established relative total shareholder return goals over a three-year period. These awards are scheduled to cliff vest on the third anniversary of the date of the grant, subject to the participant’s continuous service with the Company through the applicable vesting date and the satisfaction of the performance criteria. These awards have the potential to be distributed from 0% to 200% of target depending on actual performance. Upon vesting of these awards, the Company issues cash to the recipient. These awards are classified as a liability, and the Company reassesses at each reporting date the fair value of the award and adjusts the accruals of stock-based compensation expense as appropriate based on a Monte Carlo simulation. As of December 31, 2021, the liability for these awards totaled $255. The performance-based cash incentive awards were valued relative to the stock price performance of a comparator group and had a weighted average grant date fair value as a percent of target dollar value of 51.73% based on a Monte Carlo simulation. The Monte Carlo simulation incorporates the assumptions as presented in the following table:
Performance-based cash incentive awards
Start price (1)
$11.81 
Valuation date stock price (2)
$11.34 
Expected volatility (3)
98.54 %
Risk-free interest rate (4)
0.18 %
Expected dividend yield (5)
— %
(1)    The start price for the Company represents the average closing stock price over the twenty trading days ending on December 31, 2020, assuming dividends distributed during this period were reinvested in additional shares of the Company’s stock on the ex-dividend date.
(2)    The valuation date stock price represents the closing price at each reporting date.
(3)    The expected volatility assumption is based on the historical volatility of the price of the Company’s stock.
(4)    The annual risk-free interest rate equals the yield on the semi-annual zero coupon U.S. Treasury rates converted to continuously compounded rates that have a term equal to the length of the remaining performance measurement period as of the valuation date.
(5)    The expected dividend yield represents the investments return to a share of the Company’s stock that is not available to the holder of the performance-based restricted stock unit.

2020 Awards Granted
During the year ended December 31, 2020, the Company granted certain key employees and non-employee directors 402,620 time-based restricted stock units under the MIP and LTIP with a weighted average grant date fair value of $6.17 based on the Company’s closing stock price at the trading day before the date of the grant. The awards granted to key employees will vest ratably over a three-year period from date of grant in accordance with the vesting schedule, subject to the participant’s continuous service with the Company through each applicable vesting date. The awards granted to non-employee directors will vest on the first to occur of (i) April 30, 2021, (ii) the director’s separation from service due to the director’s death or physical or mental incapacity to perform his or her usual duties, such condition likely to remain continuously and permanently, as determined by the Company, (iii) a change in control, and (iv) the director's service as a member of the board of directors is terminated as of a date that is after October 31, 2021 but prior to May 1, 2022 for any reason other than removal for cause. Upon vesting and settlement of time-based restricted stock units, the Company issues authorized and unissued shares of the Company’s common stock to the recipient.
Additionally, during the year ended December 31, 2020, the Company granted the Chief Executive Officer (“CEO”) 302,795 performance-based restricted stock units granted under the LTIP which represent the number of shares of common stock that may be issued based on the achievement of targeted performance levels related to pre-established relative total shareholder return goals and annually determined operational goals over a three year period. This award was scheduled to cliff vest on the third anniversary of the date of the grant, subject to the participant’s continuous service with the Company through the applicable vesting date and the satisfaction of the performance criteria. These performance-based restricted stock units had the potential to be earned from 0% to 200% of target depending on actual results. Upon vesting of this award, the Company would issue authorized and previously unissued shares of the Company’s common stock to the recipient. The 151,398 operational performance-based restricted stock units were valued based on the Company’s closing stock price at the trading day before the date of the grant and had a weighted average grant date fair value of $6.36. For the awards with operational performance conditions, the Company reassessed at each reporting date whether achievement of each of the performance conditions was probable and adjusted the accrual of stock-based compensation expense as needed. The 151,397 relative total shareholder return performance-based restricted stock units were valued relative to the stock price performance of a comparator group and had a weighted average grant date fair value of $8.53 based on a Monte Carlo simulation. The Monte Carlo simulation incorporated the assumptions as presented in the following table:
Relative performance-based restricted stock units
Start price (1)
$7.59 
Valuation date stock price (2)
$6.33 
Expected volatility (3)
55.27 %
Risk-free interest rate (4)
1.37 %
Expected dividend yield (5)
— %
(1)    The start price for the Company represented the average closing stock price over the twenty trading days ending on December 31, 2019, assuming dividends distributed during this period were reinvested in additional shares of the Company’s stock on the ex-dividend date.
(2)    The valuation date stock price represented the closing price on the grant date.
(3)    The expected volatility assumption was based on the historical volatility of the price of the Company’s stock.
(4)    The annual risk-free interest rate equaled the yield on the semi-annual zero coupon U.S. Treasury rates converted to continuously compounded rates that had a term equal to the length of the remaining performance measurement period as of the valuation date.
(5)    The expected dividend yield represented the investments return to a share of the Company’s stock that is not available to the holder of the performance-based restricted stock unit.
During the first quarter of 2021, the 302,795 performance-based restricted stock units granted under the LTIP were voluntarily forfeited by the CEO in conjunction with an amendment to his employment agreement and the shares were cancelled and allocated back to the LTIP for future issuance. The amendment also included an amendment to the participant’s time-based restricted stock granted under the MIP, such that the ratable vesting initially scheduled to occur on the second and third anniversaries of the award shall instead both occur on the second anniversary of the award.

Additionally, the Company granted certain key employees performance-based cash incentive awards granted under the LTIP with a target award amount of $2,755. The cash to be awarded is based on the achievement of pre-established relative total shareholder return goals over a three-year period. These awards are scheduled to cliff vest on the third anniversary of the date of the grant, subject to the participant’s continuous service with the Company through the applicable vesting date and the satisfaction of the performance criteria. These awards have the potential to be distributed from 0% to 200% of target depending on actual performance. Upon vesting of these awards, the Company issues cash to the recipient. These awards are classified as a liability, and the Company reassesses at each reporting date the fair value of the award and adjusts the accruals of stock-based compensation expense as appropriate based on a Monte Carlo simulation. As of December 31, 2021 and 2020, the liability for these awards totaled $2,542 and $643, respectively. The performance-based cash incentive awards were valued relative to the stock price performance of a comparator group and had a weighted average grant date fair value as a percent of target dollar value of 82.45% based on a Monte Carlo simulation. The Monte Carlo simulation incorporates the assumptions as presented in the following table:
Performance-based cash incentive awards
Start price (1)
$7.59 
Valuation date stock price (2)
$6.33 
Expected volatility (3)
55.27 %
Risk-free interest rate (4)
1.37 %
Expected dividend yield (5)
— %
(1)    The start price for the Company represents the average closing stock price over the twenty trading days ending on December 31, 2019, assuming dividends distributed during this period were reinvested in additional shares of the Company’s stock on the ex-dividend date.
(2)    The valuation date stock price represents the closing price at each reporting date.
(3)    The expected volatility assumption is based on the historical volatility of the price of the Company’s stock.
(4)    The annual risk-free interest rate equals the yield on the semi-annual zero coupon U.S. Treasury rates converted to continuously compounded rates that have a term equal to the length of the remaining performance measurement period as of the valuation date.
(5)    The expected dividend yield represents the investments return to a share of the Company’s stock that is not available to the holder of the performance-based restricted stock unit.

Restricted Stock Units

Time-Based Restricted Stock Units

Time-based restricted stock unit activity for the year ended December 31, 2021 is summarized in the following table: 
Time-based restricted stock unit activity:Number of  SharesWeighted-Average Grant  Date Fair Value
Non-vested shares outstanding at December 31, 2020367,553 $13.72 
Granted223,496 $12.03 
Vested (1)
(193,854)$16.05 
Forfeited(4,920)$19.22 
Non-vested shares outstanding at December 31, 2021392,275 $11.54 
(1) Includes 61,646 shares with deferred settlement pursuant to the award agreements.

As of December 31, 2021, there was $1,167 of unrecognized compensation cost related to non-vested time-based restricted stock units which is expected to be recognized as expense over a weighted-average period of 1.33 years.
Performance-Based Restricted Stock Units

Relative performance-based restricted stock unit activity for the year ended December 31, 2021 based on target achievement of the performance criteria is summarized in the following table: 
Relative performance-based restricted stock unit activity:Number of  SharesWeighted-Average Grant  Date Fair Value
Non-vested shares outstanding at December 31, 2020174,203 $16.01 
Granted67,035 $16.18 
Vested— $— 
Forfeited or Cancelled(153,016)$9.13 
Non-vested shares outstanding at December 31, 2021 (1)
88,222 $28.07 
(1) During the first quarter of 2022, 46,551 shares were cancelled and allocated back to the LTIP for future issuance as the 2019 award’s performance metric was not achieved.

As of December 31, 2021, there was $803 of unrecognized compensation cost related to non-vested relative performance-based restricted stock units which is expected to be recognized as expense over a weighted-average period of 1.95 years.
Absolute performance-based restricted stock unit activity for the year ended December 31, 2021 based on target achievement of the performance criteria is summarized in the following table: 
Absolute performance-based restricted stock unit activity:Number of SharesWeighted-Average Grant  Date Fair Value
Non-vested shares outstanding at December 31, 20207,614 $50.60 
Granted— $— 
Vested— $— 
Forfeited(541)$50.60 
Non-vested shares outstanding at December 31, 2021 (1)
7,073 $50.60 
(1) During the first quarter of 2022, 15,532 shares were cancelled and allocated back to the LTIP for future issuance as the 2019 award’s performance metric was not achieved.

As of December 31, 2021, there was $13 of unrecognized compensation cost related to non-vested absolute performance-based restricted stock units which is expected to be recognized as expense over a weighted-average period of 0.11 years.
Operational performance-based restricted stock unit activity for the year ended December 31, 2021 based on target achievement of the performance criteria is summarized in the following table: 
Operational performance-based restricted stock unit activity:
Number of  SharesWeighted-Average Fair Value
Non-vested shares outstanding at December 31, 2020151,398 $6.36 
Granted100,552 $12.00 
Vested— $— 
Cancelled(151,398)$6.36 
Non-vested shares outstanding at December 31, 2021100,552 $12.00 

As of December 31, 2021, there was $386 of unrecognized compensation cost related to non-vested operational performance-based restricted stock units, based on the probability of achievement as of December 31, 2021, which is expected to be recognized as expense over a weighted-average period of 2.08 years.
Stock Options
30-Day Volume-Weighted Average Price (“VWAP”) Stock Options
30-day VWAP stock option activity for the year ended December 31, 2021 is summarized in the following table:
Number of SharesWeighted-Average Exercise Price Per ShareWeighted-Average Remaining Contractual Term (Years)
Aggregate Intrinsic Value (1)
Outstanding at December 31, 202023,225 $60.20 6.12$(1,134)
Exercisable at December 31, 202023,225 $60.20 6.12$(1,134)
Granted— $— 
Exercised— $— $— 
Forfeited or Expired— $— 
Outstanding at December 31, 202123,225 $60.20 5.12$20 
Exercisable at December 31, 202123,225 $60.20 5.12$20 
(1) The aggregate intrinsic value of outstanding and exercisable options is calculated as the difference between the exercise price and the Company’s stock price at each reporting period end. The aggregate intrinsic value of exercised options is calculated as the difference between the exercise price and the Company’s stock price on the exercise date.

As of December 31, 2021, there was $0 of unrecognized compensation cost related to the 30-day VWAP stock options.

Performance-Based Cash Incentive Awards
Performance-based cash incentive award activity for the year ended December 31, 2021 based on target achievement of the performance criteria is summarized in the following table: 
Performance-based cash incentive award activity:Target Dollar ValueWeighted-Average Fair Value as a % of Target Dollar Value
Non-vested awards outstanding at December 31, 2020$2,206 94.21 %
Granted927 51.73 %
Vested— — %
Forfeited(142)78.45 %
Non-vested awards outstanding at December 31, 2021$2,991 162.03 %

As of December 31, 2021, there was $2,092 of unrecognized compensation cost related to non-vested performance-based cash incentive awards, based on the probability of achievement as of December 31, 2021, which is expected to be recognized as expense over a weighted-average period of 1.39 years.
v3.22.0.1
Related Party Transactions
 12 Months Ended
Dec. 31, 2021
Related Party Transactions [Abstract]  
Related Party Transactions Related Party Transactions
There were no material related party transactions for the years ended December 31, 2021 and 2020. However, during the year ended December 31, 2021,

•the Company, through a privately negotiated transaction with an underlying Contingent Revenue Obligation creditor, repurchased 7.75% of the outstanding rights of the Contingent Revenue Obligation at an aggregate purchase price of $2,091. The underlying Contingent Revenue Obligation creditor was an existing shareholder (related party) as of the repurchase date. Refer to Note 15 for additional disclosures on this acquisition-related obligation; and
•the Company repurchased at a discount certain outstanding principal borrowings made under the Term Loan Credit Facility from existing shareholders through privately negotiated transactions. Refer to Note 14 for additional disclosures on long-term debt.
v3.22.0.1
Commitments and Contingencies
 12 Months Ended
Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]  
Commitments and Contingencies Commitments and Contingencies
(a) General
Estimated losses from loss contingencies are accrued by a charge to income when information available indicates that it is probable that an asset has been impaired or a liability has been incurred and the amount of the loss can be reasonably estimated.
If a loss contingency is not probable or reasonably estimable, disclosure of the loss contingency is made in the Consolidated Financial Statements when it is at least reasonably possible that a loss may be incurred and that the loss could be material.
(b) Commitments and Contingencies
Commitments
The Company leases coal mining and other equipment under long-term financing and operating leases with varying terms. Refer to Note 12 for further information on leases. In addition, the Company leases mineral interests and surface rights from landowners under various terms and royalty rates.
Coal royalty expense was $113,685 and $67,992 for the years ended December 31, 2021 and 2020, respectively.

Minimum royalty obligations under coal leases total $14,665, $14,418, $13,620, $12,525, $12,396, and $56,771 for 2022, 2023, 2024, 2025, 2026, and after 2026, respectively.

Other Commitments

As of December 31, 2021, the Company has obligations under certain coal purchase agreements that contain minimum quantities to be purchased in 2022 totaling an estimated $37,335. The Company also has obligations under certain coal transportation agreements that contain minimum quantities to be shipped during contract periods in 2022 and 2023 with estimated cash settlements in 2022, 2023, and 2024 which are based on estimated remaining tons to be shipped, totaling $2,527, $105,750, and $87,825, respectively. The Company also has obligations under certain equipment purchase agreements that contain minimum quantities to be purchased in 2022 totaling $18,497. Additionally, the Company has diesel fuel purchase commitments totaling $25,490 in 2022.

Contingencies
Extensive regulation of the impacts of mining on the environment and of maintaining workplace safety has had, and is expected to continue to have, a significant effect on the Company’s costs of production and results of operations. Further regulations, legislation or litigation in these areas may also cause the Company’s sales or profitability to decline by increasing costs or by hindering the Company’s ability to continue mining at existing operations or to permit new operations.
During the normal course of business, contract-related matters arise between the Company and its customers. When a loss related to such matters is considered probable and can reasonably be estimated, the Company records a liability.
Refer to Note 3 for disclosures on the Cumberland Back-to-Back Coal Supply Agreements.
(c) Guarantees and Financial Instruments with Off-Balance Sheet Risk
In the normal course of business, the Company is a party to certain guarantees and financial instruments with off-balance sheet risk, such as bank letters of credit, performance or surety bonds, and other guarantees and indemnities related to the obligations of affiliated entities which are not reflected in the Company’s Consolidated Balance Sheets. However, the underlying liabilities that they secure, such as asset retirement obligations, workers’ compensation liabilities, and royalty obligations, are reflected in the Company’s Consolidated Balance Sheets.
The Company is required to provide financial assurance in order to perform the post-mining reclamation required by its mining permits, pay workers’ compensation claims under workers’ compensation laws in various states, pay federal black lung benefits, and perform certain other obligations. In order to provide the required financial assurance, the Company generally uses surety bonds for post-mining reclamation and workers’ compensation obligations. The Company can also use bank letters of credit to collateralize certain obligations.

As of December 31, 2021, the Company had $121,037 in letters of credit outstanding under the Second Amended and Restated Asset-Based Revolving Credit Agreement. Additionally, as of December 31, 2021, the Company had $613 in letters of credit outstanding under the Credit and Security Agreement dated June 30, 2017, and related amendments, between ANR, Inc. and First Tennessee Bank National Association. On March 31, 2021, the Amended and Restated Letter of Credit Agreement dated November 9, 2018 between ANR, Inc. and Citibank, N.A. was terminated.

As of December 31, 2021, the Company had outstanding surety bonds with a total face amount of $176,119 to secure various obligations and commitments, including $30 attributable to discontinued operations. To secure the Company’s reclamation-related obligations, the Company currently has $36,792 of collateral in the form of restricted cash, restricted investments, and deposits and $15,548 of letters of credit outstanding supporting these obligations as of December 31, 2021.

The Company meets frequently with its surety providers and has discussions with certain providers regarding the extent of and the terms of their participation in the program. These discussions may cause the Company to shift surety bonds between providers or to alter the terms of their participation in our program. To the extent that surety bonds become unavailable or the Company’s surety bond providers require additional collateral, the Company would seek to secure its obligations with letters of credit, cash deposits or other suitable forms of collateral. The Company’s failure to maintain, or inability to acquire, surety bonds or to provide a suitable alternative would have a material adverse effect on its liquidity. These failures could result from a variety of factors including lack of availability, higher cost or unfavorable market terms of new surety bonds, and the exercise by third-party surety bond issuers of their right to refuse to renew the surety.

Amounts included in restricted cash represent cash deposits primarily invested in interest-bearing accounts that are restricted as to withdrawal as required by certain agreements entered into by the Company and provide collateral to secure the following obligations which have been written on the Company’s behalf:

December 31, 2021December 31, 2020
Workers’ compensation and black lung obligations$70,637 $69,725 
Reclamation-related obligations10,449 8,445 
Financial payments and other performance obligations8,340 17,863 
Contingent Revenue Obligation escrow11,977 9,311 
Total restricted cash101,403 105,344 
Less current portion (1)
(11,977)(9,311)
Restricted cash, net of current portion$89,426 $96,033 
(1) Included within Prepaid expenses and other current assets on the Company’s Consolidated Balance Sheets.

Restricted investments consist of FDIC insured certificates of deposit, mutual funds, and U.S. treasury bills that are restricted as to withdrawal as required by certain agreements entered into by the Company and provide collateral to secure the following obligations which have been written on the Company’s behalf:

December 31, 2021December 31, 2020
Workers’ compensation obligations$210 $51 
Reclamation-related obligations26,225 22,233 
Financial payments and other performance obligations2,008 1,484 
Total restricted investments (1), (2)
$28,443 $23,768 
(1) Included within Other non-current assets on the Company’s Consolidated Balance Sheets.
(2) As of December 31, 2021 and 2020, respectively, $28,443 and $22,498 are classified as trading securities and $0 and $1,270 are classified as held-to-maturity securities.
Deposits represent cash deposits held at third parties as required by certain agreements entered into by the Company to provide cash collateral to secure the following obligations which have been written on the Company’s behalf:
December 31, 2021December 31, 2020
Reclamation-related obligations$118 $25,633 
Financial payments and other performance obligations403 1,596 
Other operating agreements873 1,018 
Total deposits (1)
$1,394 $28,247 
(1) Included within Prepaid expenses and other current assets and other non-current assets on the Company’s Consolidated Balance Sheets.

DCMWC Reauthorization Process

In July 2019, the U.S. Department of Labor (Division of Coal Mine Workers’ Compensation or “DCMWC”) began implementing a new authorization process for all self-insured coal mine operators. As requested by the DCMWC, the Company filed an application and supporting documentation for reauthorization to self-insure certain of its black lung obligations in October 2019. As a result of this application, the DCMWC notified the Company in a letter dated February 21, 2020 that the Company was reauthorized to self-insure certain of its black lung obligations for a period of one-year from February 21, 2020. The DCMWC reauthorization is contingent, however, upon the Company’s providing collateral of $65,700 to secure certain of its black lung obligations. This proposed collateral requirement is an increase from the approximate $2,600 in collateral that the Company currently provides to secure these self-insured black lung obligations. The reauthorization process provided the Company with the right to appeal the security determination in writing within 30 days of the date of the notification, which appeal period the DCMWC agreed to extend to May 22, 2020. The Company exercised this right of appeal in connection with the substantial increase in the amount of required collateral. In February 2021, the U.S. Department of Labor (“DOL”) withdrew its Federal Register notice seeking comments on its bulletin describing its new method of calculating collateral requirements. The Department removed the bulletin from its website in May 2021. On February 10, 2022, a telephone conference was held with DCMWC and DOL decision makers wherein the Company presented facts and arguments in support of its appeal. No ruling has been made on the appeal, but during the call the Company indicated that it would be willing to allocate an additional $10,000 in collateral. If the Company’s appeal is unsuccessful, the Company may be required to provide additional letters of credit to receive the self-insurance reauthorization from the DCMWC or alternatively insure these black lung obligations through a third party provider that would likely also require the Company to provide additional collateral. Either of these outcomes could potentially reduce the Company’s liquidity.

(d) Legal Proceedings 

The Company is party to legal proceedings from time to time. These proceedings, as well as governmental examinations, could involve various business units and a variety of claims including, but not limited to, contract disputes, personal injury claims, property damage claims (including those resulting from blasting, trucking and flooding), environmental and safety issues, securities-related matters and employment matters. While some legal matters may specify the damages claimed by the plaintiffs, many seek an unquantified amount of damages. Even when the amount of damages claimed against the Company or its subsidiaries is stated, (i) the claimed amount may be exaggerated or unsupported; (ii) the claim may be based on a novel legal theory or involve a large number of parties; (iii) there may be uncertainty as to the likelihood of a class being certified or the ultimate size of the class; (iv) there may be uncertainty as to the outcome of pending appeals or motions; and/or (v) there may be significant factual issues to be resolved. As a result, if such legal matters arise in the future, the Company may be unable to estimate a range of possible loss for matters that have not yet progressed sufficiently through discovery and development of important factual information and legal issues. The Company records accruals based on an estimate of the ultimate outcome of these matters, but these estimates can be difficult to determine and involve significant judgment.
v3.22.0.1
Concentration of Credit Risk and Major Customers
 12 Months Ended
Dec. 31, 2021
Risks and Uncertainties [Abstract]  
Concentration of Credit Risk and Major Customers Concentration of Credit Risk and Major Customers The Company markets produced, processed, and purchased coal to customers in the United States and in international markets, primarily India, China, and Brazil. The following table presents additional information on our total revenues and top customers:
Year Ended December 31,
 20212020
Total revenue$2,258,586 $1,416,187 
Top customer as % of total revenue 13 %16 %
Top 10 customers as % of total revenue 64 %63 %
Number of customers exceeding 10% of total revenue2 2 
Number of customers exceeding 10% of total trade accounts receivable, net3 3 
Domestic revenue as % of coal revenue 24 %36 %
Export revenue as % of coal revenue 76 %64 %
Countries with export revenue exceeding 10% of total revenue India, China, BrazilIndia, Brazil
Met coal as % of coal sales volume83 %80 %
Thermal coal as % of coal sales volume17 %20 %
v3.22.0.1
Segment Information
 12 Months Ended
Dec. 31, 2021
Segment Reporting [Abstract]  
Segment Information Segment Information
The Company extracts, processes and markets met and thermal coal from deep and surface mines for sale to steel and coke producers, industrial customers, and electric utilities. The Company conducts mining operations only in the United States with mines in Central Appalachia. The Company has one reportable segment: Met, which consists of five active mines and two preparation plants in Virginia, fourteen active mines and five preparation plants in West Virginia, as well as expenses associated with certain idled/closed mines. As of December 31, 2020, the Company had two reportable segments: CAPP - Met and CAPP - Thermal. As a result of the Company’s continued strategic focus on the production of metallurgical coal and the reduction of thermal mining operations, the Company re-evaluated its previous conclusions with respect to its segment reporting during the first quarter of 2021. To conform to the current period reportable segments presentation, the prior periods have been restated to reflect the change in reportable segments.
In addition to the one reportable segment, the All Other category includes general corporate overhead and corporate assets and liabilities, the former CAPP - Thermal operations consisting of one active mine and one preparation plant in West Virginia, and the elimination of certain intercompany activity, as well as expenses associated with certain idled/closed mines.
Reportable segment operating results are regularly reviewed by the Chief Operating Decision Maker (“CODM”), who is the Chief Executive Officer of the Company.
Segment operating results and capital expenditures from continuing operations for the year ended December 31, 2021 were as follows: 
Year Ended December 31, 2021
MetAll OtherConsolidated
Total revenues$2,176,080 $82,506 $2,258,586 
Depreciation, depletion, and amortization$99,963 $10,084 $110,047 
Amortization of acquired intangibles, net$13,671 $(427)$13,244 
Adjusted EBITDA$567,270 $(34,447)$532,823 
Capital expenditures$79,185 $4,115 $83,300 
Segment operating results and capital expenditures from continuing operations for the year ended December 31, 2020 were as follows: 
Year Ended December 31, 2020
MetAll OtherConsolidated
Total revenues$1,264,496 $151,691 $1,416,187 
Depreciation, depletion, and amortization$124,060 $15,825 $139,885 
Amortization of acquired intangibles, net$12,889 $(3,675)$9,214 
Adjusted EBITDA$120,281 $(36,880)$83,401 
Capital expenditures$111,745 $7,834 $119,579 

The following table presents a reconciliation of net income (loss) from continuing operations to Adjusted EBITDA for the year ended December 31, 2021:
Year Ended December 31, 2021
MetAll OtherConsolidated
Net income (loss) from continuing operations$439,859 $(152,930)$286,929 
Interest expense184 69,470 69,654 
Interest income(6)(328)(334)
Income tax expense— 3,609 3,609 
Depreciation, depletion and amortization99,963 10,084 110,047 
Non-cash stock compensation expense28 5,287 5,315 
Mark-to-market adjustment - acquisition-related obligations— 19,525 19,525 
Gain on settlement of acquisition-related obligations— (1,125)(1,125)
Accretion on asset retirement obligations13,571 12,949 26,520 
Asset impairment and restructuring — (561)(561)
Amortization of acquired intangibles, net13,671 (427)13,244 
Adjusted EBITDA $567,270 $(34,447)$532,823 
The following table presents a reconciliation of net loss from continuing operations to Adjusted EBITDA for the year ended December 31, 2020:
Year Ended December 31, 2020
MetAll OtherConsolidated
Net loss from continuing operations$(77,519)$(163,951)$(241,470)
Interest expense(2,014)76,542 74,528 
Interest income(63)(6,964)(7,027)
Income tax benefit— (2,164)(2,164)
Depreciation, depletion and amortization124,060 15,825 139,885 
Non-cash stock compensation expense289 4,607 4,896 
Mark-to-market adjustment - acquisition-related obligations— (8,750)(8,750)
Accretion on asset retirement obligations14,214 12,290 26,504 
Asset impairment and restructuring 46,317 37,561 83,878 
Management restructuring costs (1)
501 440 941 
Loss on partial settlement of benefit obligations1,607 1,359 2,966 
Amortization of acquired intangibles, net12,889 (3,675)9,214 
Adjusted EBITDA $120,281 $(36,880)$83,401 
(1) Management restructuring costs are related to severance expense associated with senior management changes during the three months ended March 31, 2020.

No asset information has been disclosed as the CODM does not regularly review asset information by reportable segment.
v3.22.0.1
Subsequent Events
 12 Months Ended
Dec. 31, 2021
Subsequent Events [Abstract]  
Subsequent Events Subsequent EventsOn March 4, 2022, the Company’s board of directors adopted a share repurchase program that permits the Company to repurchase up to an aggregate amount of $150,000 of the Company's common stock. Share repurchases may be made from time to time through open market transactions, block trades, tender offers, or otherwise. Repurchases under the program are subject to market and business conditions, levels of available liquidity, the Company’s cash needs, restrictions under agreements or obligations, legal or regulatory requirements or restrictions and other relevant factors.
v3.22.0.1
Summary of Significant Accounting Policies (Policies)
 12 Months Ended
Dec. 31, 2021
Accounting Policies [Abstract]  
Basis of Presentation
Basis of Presentation

Together, the consolidated balance sheets and consolidated statements of operations, comprehensive income (loss), cash flows and stockholders’ equity for the Company are referred to as the “Financial Statements.” The Financial Statements are also referred to as “Consolidated” and references across periods are generally labeled “Balance Sheets,” “Statements of Operations,” and “Statements of Cash Flows.” The Company’s former Northern Appalachia (“NAPP”) operations results of operations and financial position are reported as discontinued operations in the Consolidated Financial Statements. Refer to Note 3 for further information on discontinued operations.
The Consolidated Financial Statements include all wholly owned subsidiaries’ results of operations for the years ended December 31, 2021 and 2020. All significant intercompany transactions have been eliminated in consolidation.
The accompanying Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”).
Reclassifications ReclassificationsCertain amounts in the prior year Consolidated Statements of Cash Flows have been reclassified to conform to the current year presentation.
Liquidity Risks and Uncertainties Liquidity Risks and UncertaintiesThe Company believes it will have sufficient liquidity to meet its working capital requirements, anticipated capital expenditures, debt service requirements, acquisition-related obligations, and reclamation obligations for the 12 months subsequent to the issuance of these financial statements. However, the Company may need to raise additional funds if market conditions deteriorate and may not be able to do so in a timely fashion, or at all. The Company relies on a number of assumptions in budgeting for future activities. These include the costs for mine development to sustain capacity of its operating mines, cash flows from operations, effects of regulation and taxes by governmental agencies, mining technology improvements and reclamation costs. These assumptions are inherently subject to significant business, political, economic, regulatory, environmental and competitive uncertainties, pending and existing climate-related initiatives, contingencies and risks, all of which are difficult to predict and many of which are beyond the Company’s control. Therefore, the Company’s cash on hand and from future operations will be subject to any significant changes in these assumptions.
Use of Estimates
Use of Estimates

The preparation of the Company’s Consolidated Financial Statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the Consolidated Financial Statements and the reported amounts of revenues and expenses during the reporting period. Significant items subject to such estimates and assumptions include inventories; mineral reserves and resources; long-lived asset impairments; reclamation obligations; post-employment and other employee benefit obligations; useful lives, depletion and amortization; reserves for workers’ compensation and black lung claims; deferred income taxes; income taxes refundable and receivable; reserves for contingencies and litigation; fair value of financial instruments; and fair value adjustments for acquisition accounting. Estimates are based on facts and circumstances believed to be reasonable at the time; however, actual results could differ from those estimates.
Cash and Cash Equivalents Cash and Cash Equivalents Cash and cash equivalents consist of cash held with reputable depository institutions and highly liquid, short-term investments, such as highly-rated money market funds, with original maturities of three months or less. Cash and cash equivalents are stated at cost, which approximates fair value.
Restricted Cash Restricted CashAmounts included in restricted cash represent cash deposits primarily invested in interest-bearing accounts that are restricted as to withdrawal as required by certain agreements entered into by the Company and provide collateral to secure the certain obligations which have been written on the Company’s behalf. Refer to Note 22 for further information.
Restricted Investments
Restricted Investments

Restricted investments consist of Federal Deposit Insurance Company (“FDIC”) insured certificates of deposit, mutual funds, and U.S. treasury bills classified as either trading securities or held-to-maturity securities that are restricted as to withdrawal as required by certain agreements entered into by the Company and provide collateral to secure certain obligations which have been written on the Company’s behalf.
Trading securities are recorded initially at cost and are adjusted to fair value at each reporting period with unrealized gains and recorded in current period earnings or loss. Held-to-maturity securities are recorded at amortized cost with interest income recorded in current period earnings. Given the nature of the underlying investments, the Company does not expect any credit losses and has not recorded any credit losses with respect to its held-to-maturity portfolio. Refer to Note 22 for further information.
Deposits DepositsDeposits represent cash deposits held at third parties as required by certain agreements entered into by the Company to provide cash collateral to secure the following obligations which have been written on the Company’s behalf. Refer to Note 22 for further information.
Trade Accounts Receivable and Allowance for Doubtful Accounts Trade Accounts Receivable and Allowance for Doubtful Accounts Trade accounts receivable are recorded at their invoiced amounts and do not bear interest. The Company markets its coal primarily to domestic and international steel producers and electric utilities in the United States. Credit is extended based on an evaluation of a customer’s financial condition, including a review of third-party credit score information. Collateral is generally not required. Accounts receivable balances are monitored against approved credit limits. Credit limits are monitored and adjusted as considered necessary based on changes to a customer’s credit profile. If a customer’s credit deteriorates, the Company may reduce credit risk exposure by reducing credit limits, obtaining letters of credit, obtaining credit insurance, or requiring pre-payment for shipments. Credit losses have historically not been material. Account balances are written-off against the allowance after all means of collection have been exhausted and the potential for recovery is considered remote. Refer to Note 23 for further information.
Inventories
Inventories

Coal is reported as inventory at the point in time the coal is extracted from the mine. Raw coal represents coal stockpiles that may be sold in current condition or may be further processed prior to shipment to a customer. Saleable coal represents coal stockpiles that require no further processing prior to shipment to a customer.
Coal inventories are valued at the lower of average cost or net realizable value. The cost of coal inventories is determined based on the average cost of production, which includes labor, supplies, equipment costs, operating overhead, depreciation, and other related costs. Net realizable value considers the projected future sales price of the product, less estimated preparation and selling costs. Material and supplies inventories are valued at average cost, less an allowance for obsolete and surplus items. Refer to Note 7 for further information.
Discontinued Operations
Discontinued Operations

In accordance with Accounting Standards Codification (“ASC”) 205-20-45, the Company treats a disposal transaction as a discontinued operation when the disposal of a component or group of components represents a strategic shift that will have a major effect on the Company’s operations and financial results. In the period in which the discontinued operations criteria are met, the assets and liabilities of the discontinued operations are separately presented on the Company's Consolidated Balance Sheets and the results of operations, including any gain or loss recognized, is reclassified to discontinued operations on the Company’s Consolidated Statement of Operations. Refer to Note 3 for further information.
Deferred Longwall Move Expenses Deferred Longwall Move ExpensesThe Company deferred the direct costs, including labor and supplies, associated with moving longwall equipment, the related equipment refurbishment costs, costs to drill vent holes and plug existing gas wells in advance of the longwall panel associated with its former NAPP operations included in discontinued operations during the year ending December 31, 2020. Refer to Note 3 for further information. These deferred costs were amortized on a units-of-production basis into cost of coal sales over the life of the related panel of coal mined by the longwall equipment.
Advanced Mining Royalties
Advanced Mining Royalties

Lease rights to coal reserves are often acquired in exchange for royalty payments. Advance mining royalties are advance payments made to lessors under terms of mineral lease agreements that are recoupable against future production royalties. These advance payments are deferred and charged to operations as the coal reserves are mined. The Company regularly reviews recoverability of advance mining royalties and establishes or adjusts the allowance for advance mining royalties as necessary using the specific identification method. Advance royalty balances are generally charged off against the allowance when they are no longer recoupable. Refer to Note 11 for further information.
Property, Plant and Equipment, Net
Property, Plant, and Equipment, Net

Costs for mine development incurred to expand capacity of operating mines or to develop new mines are capitalized and charged to operations on the units-of-production method over the estimated proven and probable reserve tons directly benefiting from the capital expenditures. Mine development costs include costs incurred for site preparation and development of the mines during the development stage less any incidental revenue generated during the development stage. Mining equipment, buildings, and other fixed assets are stated at cost and depreciated on a straight-line basis over estimated useful lives ranging from one to 25 years. Leasehold improvements are amortized using the straight-line method, over the shorter of the estimated
useful lives or term of the lease. Major repairs and betterments that significantly extend original useful lives or improve productivity are capitalized and depreciated over the period benefited. Maintenance and repairs are expensed as incurred. When equipment is retired or disposed, the related cost and accumulated depreciation are removed from the respective accounts and any profit or loss on disposal is recognized in other (income) expense in the Company’s Consolidated Statements of Operations.
Owned and Leased Mineral Rights Costs to obtain owned and leased mineral rights are capitalized and amortized to operations as depletion expense using the units-of-production method. Only proven and probable reserves are included in the depletion base.
Leases LeasesIn accordance with ASC 842, the Company recognizes right of use assets and lease liabilities on the Consolidated Balance Sheets for all leases with a term longer than 12 months. Some of these leases include both lease and non-lease components which are accounted for as a single lease component as the Company has elected the practical expedient to combine these components for all leases. The discount rates used to determine the present value of the lease assets and liabilities are based on the Company’s incremental borrowing rate at the lease commencement date and commensurate with the remaining lease term. As the rates implicit in most of the Company’s leases are not readily determinable, the Company uses a collateralized incremental borrowing rate based on the information available at the lease commencement date in determining the present value of future payments. The Company uses the portfolio approach and groups leases by short-term and long-term categories, applying the corresponding incremental borrowing rates to these categories of leases. For leases with a term of 12 months or less, no right of use assets or liabilities are recognized on the Consolidated Balance Sheets and the Company recognizes the lease expense on a straight-line basis over the lease term. Additionally, the Company recognizes variable lease payments as an expense in the period incurred. The Company has elected to show net instead of gross amounts for right-of-use assets and liabilities within its Consolidated Statements of Cash Flows.
Acquired Intangibles Acquired IntangiblesThe Company has recognized assets for acquired above market-priced coal supply agreements and acquired mine permits and liabilities for acquired below market-priced coal supply agreements. The coal supply agreements were valued based on the present value of the difference between the expected net contractual cash flows based on the stated contract terms and the estimated net contractual cash flows derived from applying forward market prices at the Merger or acquisition date for new contracts of similar terms and conditions. The acquired mine permits were valued based on the replacement cost and lost profits method as of the Merger date.The acquired mine permits are amortized over the estimated life of the associated mine. The coal supply agreement assets and liabilities were amortized over the actual number of tons shipped over the life of each contract.
Asset Impairment
Asset Impairment

Long-lived assets, such as property, plant, and equipment, mineral rights, and acquired intangibles subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or asset groups may not be recoverable. Recoverability of assets or asset groups to be held and used is measured by a comparison of the carrying amount of an asset or asset group to the estimated undiscounted future cash flows expected to be generated by the asset or asset group. Long-lived assets located in a close geographic area are grouped together for purposes of impairment testing when, after considering revenue and cost interdependencies, circumstances indicate the assets are used together to produce future cash flows. The Company’s asset groups generally consist of the assets and applicable liabilities of one or more mines and preparation plants and associated coal reserves for which cash flows are largely independent of cash flows of other mines, preparation plants, and associated coal reserves. If the carrying amount of an asset or asset group exceeds its estimated future cash flows, the potential impairment is equal to the amount by which the carrying amount of the asset or asset group exceeds the fair value of the asset or asset group. The Company estimates the fair value of an asset group generally using discounted cash flow analysis based on estimates of future sales volumes, coal prices, production costs, and a risk-adjusted cost of capital.
These estimates generally constitute unobservable Level 3 inputs under the fair value hierarchy. The amount of impairment, if any, is allocated to the long-lived assets on a pro-rata basis, except that the carrying value of the individual long-lived assets are not reduced below their estimated fair value. Refer to Note 8 for further information.
Asset Retirement Obligations Asset Retirement ObligationsMinimum standards for mine reclamation have been established by various regulatory agencies and dictate the reclamation requirements at the Company’s operations. The Company’s asset retirement obligations consist principally of costs to reclaim acreage disturbed at surface operations and estimated costs to reclaim support acreage, treat mine water discharge, and perform other related functions at underground mines. The Company records these reclamation obligations at fair value in the period in which the legal obligation associated with the retirement of the long-lived asset is incurred. Changes to the liability at operations that are not currently being reclaimed are offset by increasing or decreasing the carrying amount of the related long-lived asset. Changes to the liability at operations that are currently being reclaimed are recorded to depreciation, depletion, and amortization. Over time, the liability is accreted and any capitalized cost is depreciated or depleted over the useful life of the related asset. To settle the liability, the obligation is paid, and any difference between the liability and the amount of cash paid is recorded within depreciation, depletion and amortization within the Consolidated Statements of Operations at the time the reclamation work is completed. The Company annually reviews its estimated future cash flows for its asset retirement obligations. Refer to Note 16 for further information.
Income Taxes Income TaxesThe Company recognizes deferred tax assets and liabilities using enacted tax rates for the effect of temporary differences between the book and tax bases of recorded assets and liabilities. Deferred tax assets are reduced by a valuation allowance if it is more likely than not that some portion or all of the deferred tax assets will not be realized. In evaluating its ability to recover deferred tax assets within the jurisdiction in which they arise, the Company considers all available positive and negative evidence, including the expected reversals of deferred tax liabilities, projected future taxable income, taxable income available via carryback to prior years, tax planning strategies, and results of recent operations. The Company assesses the realizability of its deferred tax assets, including scheduling the reversal of its deferred tax assets and liabilities, to determine the amount of valuation allowance needed. Scheduling the reversal of deferred tax asset and liability balances requires judgment and estimation. The Company believes the deferred tax liabilities relied upon as future taxable income in its assessment will reverse in the same period and jurisdiction and are of the same character as the temporary differences giving rise to the deferred tax assets that will be realized.
Deferred Financing Costs Deferred Financing CostsThe costs to obtain new debt financing or amend existing financing agreements are generally deferred and amortized to interest expense over the life of the related indebtedness or credit facility using the effective interest method. Unamortized deferred financing costs are presented in the Consolidated Balance Sheets as a direct deduction from the carrying amount of the debt liability, consistent with debt discounts or premiums. Unamortized deferred financing costs associated with undrawn credit facilities are included in the Consolidated Balance Sheets within other non-current assets.
Revenue Recognition Revenue Recognition In accordance with ASC 606 Revenue from Contracts with Customers (“ASC 606”), the Company measures revenue based on the consideration specified in a contract with a customer and recognizes revenue as a result of satisfying its promise to transfer goods or services in a contract with a customer using the following general revenue recognition five-step model: (1) identify the contract; (2) identify performance obligations; (3) determine transaction price; (4) allocate transaction price; and (5) recognize revenue. Freight and handling costs paid to third-party carriers and invoiced to coal customers are recorded as freight and handling costs and freight and handling fulfillment revenues within cost of coal sales and coal revenues, respectively.
Workers' Compensation and Pneumoconiosis (Black Lung) Benefits, Pension and Postretirement Life Insurance Benefits
Workers’ Compensation and Pneumoconiosis (Black Lung) Benefits 

Workers’ Compensation

As of December 31, 2021, the Company’s subsidiaries generally utilize high-deductible insurance programs for workers’ compensation claims at its operations with the exception of certain subsidiaries in which the Company is a qualified self-insurer
for workers’ compensation obligations. The liabilities for workers’ compensation claims are estimates of the ultimate losses incurred based on the Company’s experience and include a provision for incurred but not reported losses. Adjustments to the probable ultimate liabilities are made annually based on an actuarial study and adjustments to the liability are recorded based on the results of this study. These short-term and long-term obligations are included in the Consolidated Balance Sheets within accrued expenses and other current liabilities and workers’ compensation and black lung obligations, respectively, with the related expected insurance receivables within prepaid expenses and other current assets and other non-current assets. As of December 31, 2021 and 2020, the workers’ compensation liability was net of a discount of $23,442 and $24,061, respectively, related to fair value adjustments associated with acquisition accounting. Refer to Note 19 for further information.

Black Lung Benefits

The Company is required by federal and state statutes to provide benefits to employees for awards related to black lung. As of December 31, 2021, certain of the Company’s subsidiaries are insured for black lung obligations by a third-party insurance provider and certain subsidiaries are self-insured for state black lung obligations. Certain other subsidiaries are self-insured for federal black lung benefits and may fund benefit payments through a Section 501(c)(21) tax-exempt trust fund. Charges are made to operations for black lung claims, as determined by an independent actuary at the present value of the actuarially computed liability for such benefits over the employee’s applicable term of service. The Company recognizes in its Consolidated Balance sheets the amount of the Company’s unfunded Accumulated Benefit Obligation (“ABO”) at the end of the year. The actuarial gains and losses recognized in accumulated other comprehensive income (loss) are amortized into components of net periodic benefit cost over the expected lifetime of active participants (the Company does not use a corridor method). These short-term and long-term obligations are included in the Consolidated Balance Sheets within accrued expenses and other current liabilities and workers’ compensation and black lung obligations, respectively. Refer to Note 19 for further information.

Pension

The Company is required to recognize the overfunded or underfunded status of a defined benefit pension plan as an asset or liability in its Consolidated Balance Sheets and to recognize changes in that funded status in the year in which the changes occur through other comprehensive (loss) income. The actuarial gains and losses recognized in accumulated other comprehensive income (loss) are amortized into components of net periodic benefit cost over the average future lifetime of participants expected to have benefits (the Company does not use a corridor method). The Company is required to measure plan assets and benefit obligations as of the date of the Company’s fiscal year-end Consolidated Balance Sheet and provide the required disclosures as of the end of each fiscal year. Refer to Note 19 for information.
Postretirement Life Insurance Benefits

As part of the Alpha Natural Resources, Inc. bankruptcy reorganization plan and the Retiree Committee Settlement Agreement, the Company assumed the liability for life insurance benefits for certain disabled and non-union retired employees. Provisions are made for estimated benefits based on annual evaluations prepared by independent actuaries. Adjustments to the probable ultimate liabilities are made annually based on an actuarial study and adjustments to the liability are recorded based on the results of this study. These obligations are included in the Consolidated Balance Sheets as Accrued expenses and other current liabilities and Other non-current liabilities. Refer to Note 19 for further information.
Net Income (Loss) Per Share
Net Income (Loss) per Share

 Basic net income (loss) per share is computed by dividing net income (loss) by the weighted-average number of outstanding common shares for the period. Diluted (loss) earnings per share reflects the potential dilution that could occur if instruments that may require the issuance of common shares in the future were settled and the underlying common shares were issued. Diluted (loss) earnings per share is computed by increasing the weighted-average number of outstanding common shares computed in basic earnings (loss) per share to include the additional common shares that would be outstanding after issuance and adjusting net income (loss) for changes that would result from the issuance. Only those securities that are dilutive are included in the calculation. In periods of loss, the number of shares used to calculate diluted earnings is the same as basic earnings per share. Refer to Note 6 for further information.
Stock-Based Compensation Stock-Based CompensationThe Company recognizes expense for stock-based compensation awards based on their grant-date fair value. The expense is recorded over the respective service period of the underlying award. Liability classified stock-based compensation awards are remeasured each reporting period at fair value until the award is settled. The Company recognizes forfeitures of stock-based compensation awards as they occur. Refer to Note 20 for further information.
Warrants WarrantsOn July 26, 2016 (the “Initial Issue Date”), the Company issued 810,811 warrants, which are classified as equity instruments, each with an initial exercise price, as defined in the Series A Warrants Agreement (the “Warrants Agreement”), of $55.93 per share of common stock and exercisable for one share of the Alpha’s common stock, par value $0.01 per share. Pursuant to the Warrants Agreement, the warrants are exercisable for cash or on a cashless basis at any time from the Initial Issue Date until July 26, 2023, and no fractional shares shall be issued upon warrant exercises. The exercise price and the warrant share number will be adjusted in respect of certain dilutive events with respect to the common stock (namely, dividends or distributions on the common stock, share splits and combinations, above-market tender offers for common stock by the Company or a subsidiary thereof, and discounted issuances of common stock or rights or options to purchase common stock or securities convertible or exchangeable into common stock). Refer to Note 25 for subsequent event disclosures related to the Company’s share repurchase program. Additionally, in the case of any reorganization (i.e., a consolidation, merger, or sale of all or substantially all of the consolidated assets of Alpha) pursuant to which the common stock is converted into cash, securities or other property, the warrants would become exercisable for such property.
Equity Method Investments Equity Method InvestmentsInvestments in unconsolidated affiliates that the Company has the ability to exercise significant influence over, but not control, are accounted for under the equity method of accounting. Under the equity method of accounting, the Company records its proportionate share of the entity’s net income or loss at each reporting period in the Consolidated Statements of Operations in other (expense) income, with a corresponding entry to increase or decrease the carrying value of the investment.
Recently Adopted Accounting Guidance and Recent Accounting Guidance Issued Not Yet Effective
Recently Adopted Accounting Guidance

Business Combinations: In October 2021, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) 2021-08, Business Combinations (Topic 805), Accounting for Contract Assets and Contract Liabilities from Contracts with Customers (“ASU 2021-08”). This update requires an acquirer in a business combination to recognize and measure contract assets and contract liabilities from acquired contracts with customers using the revenue recognition guidance in ASC 606. This creates an exception to the general recognition and measurement principle in ASC 805, Business Combinations. The amendments in this update are intended to improve the accounting for acquired revenue contracts with customers in a business combination by addressing diversity in practice and certain inconsistencies. The update is effective for fiscal years beginning after December 15, 2022 and interim periods within those fiscal years for public business entities, with early adoption permitted. The Company adopted ASU 2021-08 during the fourth quarter of 2021. The adoption of this ASU did not have a material impact on the Company's Consolidated Financial Statements and related disclosures.

Presentation of Financial Statements: In August 2021, the FASB issued ASU 2021-06, Presentation of Financial Statements (Topic 205), Financial Services—Depository and Lending (Topic 942), and Financial Services—Investment Companies (Topic 946) (“ASU 2021-06”). This update amends certain SEC paragraphs from the Codification in response to the issuance of SEC Final Rule Nos. 33-10786, Amendments to Financial Disclosures About Acquired and Disposed Businesses, and 33-10835, Update of Statistical Disclosures for Bank and Savings and Loan Registrants. For all entities, the update is effective immediately. The Company adopted ASU 2021-06 during the third quarter of 2021. The adoption of this ASU did not
have a material impact on the Company's Consolidated Financial Statements and related disclosures.

Leases: In July 2021, the FASB issued ASU 2021-05, Leases (Topic 842) Lessors—Certain Leases with Variable Lease Payments (“ASU 2021-05”). The amendments in this update affect lessors with lease contracts that (1) have variable lease payments that do not depend on a reference index or a rate (“variable payments”) and (2) would have resulted in the recognition of a selling loss at lease commencement if classified as sales-type or direct financing. The amendments in this update address stakeholders’ concerns by amending the lease classification requirements for lessors to align them with practice under Topic 840 by requiring a lessor to classify a lease with variable payments as an operating lease on the commencement date of the lease if specified criteria are met. The amendments are effective for fiscal years beginning after December 15, 2021, for all entities, and interim periods within those fiscal years for public business entities with early application permitted. The Company adopted ASU 2021-05 during the third quarter of 2021. The adoption of this ASU did not have a material impact on the Company's Consolidated Financial Statements and related disclosures.

Certain Modifications or Exchanges of Freestanding Equity-Classified Written Call Options: In May 2021, the FASB issued ASU 2021-04, Earnings Per Share (Topic 260), Debt—Modifications and Extinguishments (Subtopic 470-50), Compensation—Stock Compensation (Topic 718), and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40) (“ASU 2021-04”). The amendments in this update provide final guidance that requires issuers to account for modifications or exchanges of freestanding equity-classified written call options, such as the Company’s outstanding Series A warrants, that remain equity classified after the modification or exchange based on the economic substance of the modification or exchange. This ASU addresses the diversity in practice in issuers’ accounting by providing a principles-based framework to determine whether an issuer should recognize the modification or exchange as 1) an adjustment to equity and, if so, the related earnings per share effects, if any, or 2) an expense and, if so, the manner and pattern of recognition. For all entities, the standard is effective for fiscal years beginning after December 15, 2021, with early adoption permitted. The Company adopted ASU 2021-04 during the second quarter of 2021. The adoption of this ASU did not have a material impact on the Company's Consolidated Financial Statements and related disclosures.

Reference Rate Reform: In January 2021, the FASB issued ASU 2021-01, Reference Rate Reform (Topic 848) (“ASU 2021-01”). The amendments in this update clarify that certain optional expedients and exceptions in Topic 848 for contract modifications and hedge accounting apply to derivatives that are affected by the discounting transition. For all entities, the standard is effective immediately. The Company adopted ASU 2021-01 during the first quarter of 2021. The adoption of this ASU did not have a material impact on the Company's Consolidated Financial Statements and related disclosures.

Convertible Debt and Contracts in Entity’s Own Equity: In August 2020, the FASB issued ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40) (“ASU 2020-06”). The amendments in this update simplify the accounting for certain financial instruments with characteristics of liabilities and equity, including convertible instruments and contracts in an entity’s own equity, such as the Company’s outstanding Series A warrants. For public business entities, the standard is effective for fiscal years beginning after December 15, 2021, with early adoption permitted. The Company adopted ASU 2020-06 during the first quarter of 2021. The adoption of this ASU did not have a material impact on the Company's Consolidated Financial Statements and related disclosures.

Credit Losses: In June 2016, the FASB issued ASU 2016-13, Credit Losses (“ASU 2016-13”). ASU 2016-13, along with related amendments and improvements issued in 2018 and 2019, replaces the previous incurred loss impairment methodology in U.S. GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable supportable information to inform credit loss estimates for financial instruments that are in the scope of this update, including trade accounts receivable. The Company adopted ASU 2016-13 during the first quarter of 2020. The adoption of this ASU did not have a material impact on the Company's Consolidated Financial Statements and related disclosures and resulted in a cumulative-effect adjustment to retained earnings of $440 in the Consolidated Balance Sheet as of January 1, 2020.

Recent Accounting Guidance Issued Not Yet Effective
Government Assistance: In November 2021, the FASB issued ASU 2021-10, Disclosures by Business Entities about Government Assistance (“ASU 2021-10”). This update requires business entities to make annual disclosures about transactions with a government accounted for by analogizing to a grant or contribution accounting model. The required annual disclosures include the nature of the transaction, the related accounting policy, the financial statement line items affected and the amounts reflected in the current period financial statements, and any significant terms and conditions. The amendments are effective for fiscal years beginning after December 15, 2021, for all entities, with early application permitted. The adoption of this ASU is not expected to have a material impact on the Company’s Consolidated Financial Statements and related disclosures.
v3.22.0.1
Summary of Significant Accounting Policies (Tables)
 12 Months Ended
Dec. 31, 2021
Accounting Policies [Abstract]  
Schedule of Intangibles The balances and respective Consolidated Balance Sheets classifications of such assets and liabilities as of December 31, 2021 and 2020, net of accumulated amortization, are set forth in the following tables:
December 31, 2021
Assets (1)
Liabilities (2)
Net Total
Coal supply agreements, net$— $— $— 
Acquired mine permits, net74,197 — 74,197 
Total$74,197 $— $74,197 
December 31, 2020
Assets (1)
Liabilities (2)
Net Total
Coal supply agreements, net$— $(327)$(327)
Acquired mine permits, net88,196 — 88,196 
Total$88,196 $(327)$87,869 
(1) Included within Other acquired intangibles, net of accumulated amortization, on the Company’s Consolidated Balance Sheets.
(2) Included within Other non-current liabilities on the Company’s Consolidated Balance Sheets.
The following table details the amortization of mine permits acquired as a result of the Merger and the amortization of above-market and below-market coal supply agreements.
December 31,
20212020
Amortization of mine permits (1)
$13,571 $14,887 
Amortization of above-market coal supply agreements$— $18 
Amortization of below-market coal supply agreements(327)(5,691)
Net income (1)
$(327)$(5,673)
(1) Included within amortization of acquired intangibles, net in the Consolidated Statements of Operations.
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense
Future net amortization expense related to acquired intangibles is expected to be as follows:  
2022$11,749 
20238,079 
20246,728 
20256,723 
20266,196 
Thereafter34,722 
Total net future amortization expense$74,197 
v3.22.0.1
Discontinued Operations (Tables)
 12 Months Ended
Dec. 31, 2021
Discontinued Operations and Disposal Groups [Abstract]  
Discontinued Operations
The following table presents the details of the Cumberland Transaction:
Year Ended December 31, 2020
Cash$19,987 
Surety bonding collateral30,000 
Total consideration49,987 
Transaction costs2,205 
Carrying value of assets and liabilities (1)
$(16,079)
Loss on sale$36,113 
(1) Assets and liabilities were primarily comprised of property, plant and equipment, net of $32,872, deferred longwall move expenses of $15,173, and coal and supplies inventory of $5,112 and asset retirement obligations of $39,573, severance of $17,143, black lung obligations of $8,290, and subsidence liability of $3,559.
The major components of net loss from discontinued operations before income taxes in the Consolidated Statements of Operations for the year ended December 31, 2020 are as follows:
Year Ended December 31, 2020 (1)
Revenues:
Total revenues$235,509 
Costs and expenses:
Cost of coal sales (exclusive of items shown separately below)215,390 
Depreciation, depletion and amortization11,570 
Accretion on asset retirement obligations4,154 
Asset impairment and restructuring (2)
172,640 
Selling, general and administrative expenses (3)
1,623 
Other income(926)
Other non-major expense items, net374 
Loss on sale36,113 
Loss from discontinued operations before income taxes$(205,429)
(1) Includes minor residual activity related to the Company’s former PRB operations.
(2) Refer to Note 8.
(3) Represents professional and legal fees.
The major components of assets and liabilities that are classified as discontinued operations in the Consolidated Balance Sheets are as follows:
December 31,
20212020
Assets:  
Trade accounts receivable, net of allowance for doubtful accounts$— $7,504 
Prepaid expenses and other current assets$462 $3,431 
Other non-current assets (1)
$8,526 $9,473 
Liabilities:  
Trade accounts payable, accrued expenses and other current liabilities$5,838 $12,306 
Workers’ compensation and black lung obligations, non-current$23,683 $27,799 
Other non-current liabilities$— $1,291 
(1) Primarily comprised of workers’ compensation insurance receivable and long-term restricted investments collateralizing workers’ compensation obligations.

The major components of cash flows related to discontinued operations were as follows:
Year Ended December 31,
2020
Depreciation, depletion and amortization$11,570 
Capital expenditures$34,411 
Other significant operating non-cash items related to discontinued operations:
Accretion on asset retirement obligations$4,154 
Asset impairment and restructuring$172,640 
v3.22.0.1
Revenue (Tables)
 12 Months Ended
Dec. 31, 2021
Revenue from Contract with Customer [Abstract]  
Disaggregation of Revenue The following tables disaggregate the Company’s coal revenues by product category and by market to depict how the nature, amount, timing, and uncertainty of the Company’s coal revenues and cash flows are affected by economic factors:
Year Ended December 31, 2021
Met CoalThermal CoalTotal
Export coal revenues$1,675,147 $30,879 $1,706,026 
Domestic coal revenues396,160 150,411 546,571 
Total coal revenues$2,071,307 $181,290 $2,252,597 
Year Ended December 31, 2020
Met CoalThermal CoalTotal
Export coal revenues$870,121 $27,904 $898,025 
Domestic coal revenues362,654 152,445 515,099 
Total coal revenues$1,232,775 $180,349 $1,413,124 
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction The following table includes estimated revenue expected to be recognized in the future related to performance obligations that are unsatisfied as of December 31, 2021.
20222023202420252026Total
Estimated coal revenues (1)
$65,768 $14,199 $— $— $— $79,967 
(1) Amounts only include estimated coal revenues associated with contracts with customers with fixed pricing with original expected duration of more than one year. The Company has elected not to disclose the aggregate amount of the transaction price allocated to the performance obligations that are unsatisfied (or partially unsatisfied) as of the end of the reporting period for performance obligations with either of the following conditions: 1) the remaining performance obligation is part of a contract that has an original expected duration of one year or less; or 2) the remaining performance obligation has variable consideration that is allocated entirely to a wholly unsatisfied performance obligation.
v3.22.0.1
Accumulated Other Comprehensive Loss (Tables)
 12 Months Ended
Dec. 31, 2021
Equity [Abstract]  
Schedule of Accumulated Other Comprehensive Loss
The following tables summarize the changes to accumulated other comprehensive loss during the years ended December 31, 2021 and 2020:
Balance January 1, 2021Other comprehensive income before reclassificationsAmounts reclassified from accumulated other comprehensive lossBalance December 31, 2021
Employee benefit costs$(111,985)$47,461 $6,021 $(58,503)
Balance January 1, 2020
Other comprehensive loss before reclassificationsAmounts reclassified from accumulated other comprehensive loss
Balance December 31, 2020
Employee benefit costs$(58,616)$(60,647)$7,278 $(111,985)

The following table summarizes the amounts reclassified from accumulated other comprehensive loss and the Consolidated Statements of Operations line items affected by the reclassification during the years ended December 31, 2021 and 2020:
Details about accumulated other comprehensive loss componentsAmounts reclassified from accumulated other comprehensive lossAffected line item in the Consolidated Statements of Operations
Year Ended December 31,
20212020
Employee benefit costs:
Amortization of actuarial loss (1)
$5,653 $3,929 
Miscellaneous income (loss), net
Settlement (1)
368 3,349 
Miscellaneous income (loss), net
Total before income tax$6,021 $7,278 
Income tax— — Income tax (expense) benefit
Total, net of income tax$6,021 $7,278 
(1) These accumulated other comprehensive loss components are included in the computation of net periodic benefit costs for certain employee benefit plans. Refer to Note 19.
v3.22.0.1
Net Income (Loss) per Share (Tables)
 12 Months Ended
Dec. 31, 2021
Earnings Per Share [Abstract]  
Schedule of Earnings Per Share, Basic and Diluted
The following table presents the net income (loss) per common share for the years ended December 31, 2021 and 2020:

Year Ended December 31,
20212020
Net income (loss)
Income (loss) from continuing operations$286,929 $(241,470)
Income (loss) from discontinued operations1,861 (205,429)
Net income (loss)$288,790 $(446,899)
Basic
Weighted average common shares outstanding - basic18,441,175 18,298,362 
Basic income (loss) per common share:
Income (loss) from continuing operations$15.56 $(13.20)
Income (loss) from discontinued operations0.10 (11.22)
Net income (loss)$15.66 $(24.42)
Diluted
Weighted average common shares outstanding - basic18,441,175 18,298,362 
Diluted effect of warrants35,574 — 
Diluted effect of stock options1,753 — 
Diluted effect of other stock-based instruments393,180 — 
Weighted average common shares outstanding - diluted18,871,682 18,298,362 
Diluted income (loss) per common share:
Income (loss) from continuing operations$15.20 $(13.20)
Income (loss) from discontinued operations0.10 (11.22)
Net income (loss)$15.30 $(24.42)
v3.22.0.1
Inventories, net (Tables)
 12 Months Ended
Dec. 31, 2021
Inventory Disclosure [Abstract]  
Schedule of Inventory
Inventories, net consisted of the following: 
December 31,
 20212020
Raw coal$20,347 $15,084 
Saleable coal81,240 69,262 
Materials, supplies and other, net (1)
27,795 23,705 
Total inventories, net$129,382 $108,051 
(1) Includes an increase in allowance for obsolete material and supplies inventory of $807 recorded as restructuring expense during the year ended December 31, 2020 (refer to Note 8).
v3.22.0.1
Asset Impairment and Restructuring (Tables)
 12 Months Ended
Dec. 31, 2021
Restructuring and Related Activities [Abstract]  
Details of Long-Lived Asset Impairments
The following tables present the details of the long-lived asset impairments during the year ended December 31, 2020:

Year Ended December 31, 2020
First QuarterSecond QuarterThird QuarterFourth QuarterYear Ended
Continuing operations:
Met
$32,951 $— $— $13,366 $46,317 
All Other758 17,390 219 16,270 34,637 
Total from continuing operations$33,709 $17,390 $219 $29,636 $80,954 
Discontinued operations:$— $144,348 $3,297 $— $147,645 
Total long-lived asset impairment:$33,709 $161,738 $3,516 $29,636 $228,599 
Year Ended December 31, 2020
First QuarterSecond QuarterThird QuarterFourth QuarterYear Ended
Continuing operations:
Mineral rights, net
$21,825 $2,241 $— $17,513 $41,579 
Property, plant, and equipment, net
6,066 6,496 219 5,450 18,231 
Acquired mine permits, net5,818 8,653 — 6,673 21,144 
Total from continuing operations$33,709 $17,390 $219 $29,636 $80,954 
Discontinued operations:
Mineral rights, net
$— $16,364 $— $— $16,364 
Property, plant, and equipment, net
— 127,984 3,297 — 131,281 
Total from discontinued operations$— $144,348 $3,297 $— $147,645 
Total long-lived asset impairment:
Mineral rights, net
$21,825 $18,605 $— $17,513 $57,943 
Property, plant, and equipment, net
6,066 134,480 3,516 5,450 149,512 
Acquired mine permits, net5,818 8,653 — 6,673 21,144 
Total long-lived asset impairment$33,709 $161,738 $3,516 $29,636 $228,599 
Restructuring and Related Costs
As a result of the strategic actions discussed above, the Company recorded restructuring expense during the year ended December 31, 2020 as follows:
Year Ended December 31, 2020
Total Restructuring
Continuing Operations (3)
Discontinued Operations
Severance and employee-related benefits (1)
$26,037 $2,117 $23,920 
Other costs (2)
1,882 807 1,075 
Total restructuring expense$27,919 $2,924 $24,995 

(1) Severance and employee-related benefits were considered probable and estimable based on provisions of contractual agreements and existing employee benefit plans.
(2) Includes accelerated amortization of deferred longwall move expenses of $668, allowance for advanced mining royalties of $407, and allowance for obsolete materials and supplies inventory of $807.
(3) Total restructuring expense from continuing operations of $2,924 was recorded within the All Other category and affected Accrued expenses and other current liabilities, Other non-current liabilities, Inventories, net, and Other non-current assets.
v3.22.0.1
Prepaid Expenses and Other Current Assets (Tables)
 12 Months Ended
Dec. 31, 2021
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]  
Prepaid Expenses and Other Current Assets
Prepaid expenses and other current assets consisted of the following:
December 31,
 20212020
Prepaid freight$19,671 $8,515 
Notes and other receivables4,161 13,245 
Short-term restricted cash11,977 9,311 
Prepaid insurance8,525 6,510 
Refundable income taxes— 64,565 
Prepaid bond premium1,649 2,576 
Other prepaid expenses1,707 1,530 
Total prepaid expenses and other current assets$47,690 $106,252 
Restricted investments consist of FDIC insured certificates of deposit, mutual funds, and U.S. treasury bills that are restricted as to withdrawal as required by certain agreements entered into by the Company and provide collateral to secure the following obligations which have been written on the Company’s behalf:

December 31, 2021December 31, 2020
Workers’ compensation obligations$210 $51 
Reclamation-related obligations26,225 22,233 
Financial payments and other performance obligations2,008 1,484 
Total restricted investments (1), (2)
$28,443 $23,768 
(1) Included within Other non-current assets on the Company’s Consolidated Balance Sheets.
(2) As of December 31, 2021 and 2020, respectively, $28,443 and $22,498 are classified as trading securities and $0 and $1,270 are classified as held-to-maturity securities.
Deposits represent cash deposits held at third parties as required by certain agreements entered into by the Company to provide cash collateral to secure the following obligations which have been written on the Company’s behalf:
December 31, 2021December 31, 2020
Reclamation-related obligations$118 $25,633 
Financial payments and other performance obligations403 1,596 
Other operating agreements873 1,018 
Total deposits (1)
$1,394 $28,247 
(1) Included within Prepaid expenses and other current assets and other non-current assets on the Company’s Consolidated Balance Sheets.
v3.22.0.1
Property, Plant, and Equipment, Net (Tables)
 12 Months Ended
Dec. 31, 2021
Property, Plant and Equipment [Abstract]  
Schedule of Property, Plant, and Equipment, Net
Property, plant, and equipment, net, consisted of the following: 
December 31,
 20212020
Plant and mining equipment$642,874 $603,463 
Mine development115,357 96,008 
Land26,389 26,606 
Office equipment, software and other1,462 1,379 
Construction in progress19,992 18,587 
Total property, equipment and mine development costs$806,074 $746,043 
Less accumulated depreciation, depletion and amortization(443,856)(382,423)
Total property, plant, and equipment, net$362,218 $363,620 
v3.22.0.1
Other Non-Current Assets (Tables)
 12 Months Ended
Dec. 31, 2021
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]  
Schedule of Other Non-Current Assets
Other non-current assets consisted of the following:
December 31,
 20212020
Advanced mining royalties$10,788 $13,132 
Long-term deposits1,371 28,200 
Long-term restricted investments28,443 23,768 
Equity method investments20,460 18,383 
Workers’ compensation receivables45,335 48,320 
Other24,660 17,579 
Total other non-current assets$131,057 $149,382 
v3.22.0.1
Leases (Tables)
 12 Months Ended
Dec. 31, 2021
Leases [Abstract]  
Right-of-use Assets and Lease Liabilities
As of December 31, 2021 and 2020, the Company had the following right-of-use assets and lease liabilities within the Company’s Consolidated Balance Sheets:
December 31, 2021December 31, 2020
AssetsBalance Sheet Classification
Financing lease assetsProperty, plant, and equipment, net$2,987 $4,262 
Operating lease right-of-use assetsOther non-current assets5,003 5,671 
Total lease assets$7,990 $9,933 
LiabilitiesBalance Sheet Classification
Financing lease liabilities - currentCurrent portion of long-term debt$1,878 $2,014 
Operating lease liabilities - currentAccrued expenses and other current liabilities547 595 
Financing lease liabilities - long-termLong-term debt791 1,996 
Operating lease liabilities - long-termOther non-current liabilities4,456 5,076 
Total lease liabilities$7,672 $9,681 
Lease Costs and Other Information Total lease costs and other lease information for the years ended December 31, 2021 and 2020 included the following:
Year Ended December 31, 2021Year Ended December 31, 2020
Lease cost (1)
Financing lease cost:
     Amortization of leased assets$2,061 $3,238 
     Interest on lease liabilities245 358 
Operating lease cost1,383 2,105 
Short-term lease cost786 1,518 
     Total lease cost$4,475 $7,219 
(1) The Company had no variable lease costs or sublease income for the years ended December 31, 2021 and 2020.

Year Ended December 31,
20212020
Other information
Cash paid for amounts included in the measurement of lease liabilities$4,478 $7,157 
     Operating cash flows from financing leases$245 $358 
     Operating cash flows from operating leases$2,169 $3,623 
     Financing cash flows from financing leases$2,064 $3,176 
Right-of-use assets obtained in exchange for new financing lease liabilities$703 $221 
Right-of-use assets obtained in exchange for new operating lease liabilities$275 $(12)
Lease Term and Discount Rate
Weighted-average remaining lease term in years - financing leases1.751.94
Weighted-average remaining lease term in years - operating leases7.888.45
Weighted-average discount rate - financing leases9.6 %6.1 %
Weighted-average discount rate - operating leases11.3 %11.5 %
Finance Lease Maturity
The following table summarizes the maturity of the Company’s lease liabilities on an undiscounted cash flow basis and a reconciliation to the lease liabilities recognized in the Company’s Consolidated Balance Sheets as of December 31, 2021:
Financing LeasesOperating Leases
Lease cost
2022$2,072 $1,100 
2023522 1,066 
2024259 955 
2025150 897 
20263 884 
Thereafter— 2,775 
Total future minimum lease payments$3,006 $7,677 
Imputed interest(337)(2,674)
Present value of future minimum lease payments$2,669 $5,003 
Operating Lease Maturity
The following table summarizes the maturity of the Company’s lease liabilities on an undiscounted cash flow basis and a reconciliation to the lease liabilities recognized in the Company’s Consolidated Balance Sheets as of December 31, 2021:
Financing LeasesOperating Leases
Lease cost
2022$2,072 $1,100 
2023522 1,066 
2024259 955 
2025150 897 
20263 884 
Thereafter— 2,775 
Total future minimum lease payments$3,006 $7,677 
Imputed interest(337)(2,674)
Present value of future minimum lease payments$2,669 $5,003 
v3.22.0.1
Accrued Expenses and Other Current Liabilities (Tables)
 12 Months Ended
Dec. 31, 2021
Payables and Accruals [Abstract]  
Schedule of Accrued Expenses and Other Current Liabilities
Accrued expenses and other current liabilities consisted of the following: 
December 31,
 20212020
Wages and benefits$52,310 $40,330 
Workers’ compensation 10,582 10,355 
Black lung 7,235 6,784 
Taxes other than income taxes30,734 21,540 
Current portion of asset retirement obligations32,159 24,990 
Accrued interest and fees14,489 15,902 
Deferred revenue— 13,197 
Freight accrual15,085 2,610 
Other 12,013 4,698 
Total accrued expenses and other current liabilities$174,607 $140,406 
v3.22.0.1
Long-Term Debt (Tables)
 12 Months Ended
Dec. 31, 2021
Debt Disclosure [Abstract]  
Schedule of Long-term Debt Instruments
Long-term debt consisted of the following: 
December 31,
 20212020
Term Loan Credit Facility - due June 2024$449,435 $553,373 
ABL Facility - due December 2024— 3,350 
LCC Note Payable— 27,500 
LCC Water Treatment Obligation— 6,875 
Other (1)
5,311 8,475 
Debt discount and issuance costs(6,195)(17,046)
Total long-term debt $448,551 $582,527 
Less current portion(2,989)(28,830)
Long-term debt, net of current portion$445,562 $553,697 
(1) Includes financing leases, refer to Note 12 for additional information.
Schedule of Maturities of Long-term Debt
Future maturities of long-term debt as of December 31, 2021 are as follows: 
2022$2,989 
20231,367 
2024450,245 
2025142 
20263 
Total long-term debt$454,746 
v3.22.0.1
Acquisition-Related Obligations (Tables)
 12 Months Ended
Dec. 31, 2021
Fair Value Disclosures [Abstract]  
Schedule of Acquisition-Related Obligations
Acquisition-related obligations consisted of the following:
December 31,
20212020
Contingent Revenue Obligation$35,005 $28,967 
Environmental Settlement Obligations6,633 10,391 
UMWA Funds Settlement Liability— 2,000 
Discount(233)(1,491)
Total acquisition-related obligations $41,405 $39,867 
Less current portion(22,405)(19,099)
Acquisition-related obligations, net of current portion$19,000 $20,768 
v3.22.0.1
Asset Retirement Obligations (Tables)
 12 Months Ended
Dec. 31, 2021
Asset Retirement Obligation Disclosure [Abstract]  
Summary of Changes in Asset Retirement Obligations
The following table summarizes the changes in asset retirement obligations for the years ended December 31, 2021 and 2020:
Total asset retirement obligations at December 31, 2019$203,137 
Accretion for the period 26,504 
Sites added during the period621 
Revisions in estimated cash flows (1)
(43,765)
Expenditures for the period(21,433)
Total asset retirement obligations at December 31, 2020$165,064 
Accretion for the period26,520 
Sites added during the period 2,125 
Revisions in estimated cash flows (1)
(12,744)
Expenditures for the period(16,793)
Total asset retirement obligations at December 31, 2021$164,172 
Less current portion (2)
(32,159)
Long-term portion$132,013 
(1)    The revisions in estimated cash flows resulted primarily from discount rate adjustments and changes in mine plans.
(2)    Included within Accrued expenses and other current liabilities on the Company’s Consolidated Balance Sheets. Refer to Note 13.
v3.22.0.1
Fair Value of Financial Instruments and Fair Value Measurements (Tables)
 12 Months Ended
Dec. 31, 2021
Fair Value Disclosures [Abstract]  
Fair Value Measurements, Nonrecurring
The following tables set forth by level, within the fair value hierarchy, the Company’s long-term debt at fair value as of December 31, 2021 and 2020:
December 31, 2021
Carrying
     Amount (1)
Total Fair
Value		Quoted Prices in Active Markets (Level 1)Significant Other Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Term Loan Credit Facility - due June 2024$443,241 $447,561 $— $447,561 $— 
Total long-term debt$443,241 $447,561 $— $447,561 $— 

December 31, 2020
Carrying
Amount (1)
Total Fair
Value		Quoted Prices in Active Markets (Level 1)Significant Other Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Term Loan Credit Facility - due June 2024$540,643 $379,614 $— $379,614 $— 
ABL Facility - due April 2022 (2)
3,350 3,057 — — 3,057 
LCC Note Payable24,423 20,328 — — 20,328 
LCC Water Treatment Obligation5,636 4,281 — — 4,281 
Total long-term debt$574,052 $407,280 $— $379,614 $27,666 
(1) Net of debt discounts and debt issuance costs.
(2) On December 6, 2021, the Company entered into a New ABL Agreement. Refer to Note 14 for additional information.

The following tables set forth by level, within the fair value hierarchy, the Company’s acquisition-related obligations at fair value as of December 31, 2021 and 2020:
 December 31, 2021
Carrying
Amount (1)
Total Fair ValueQuoted Prices in Active Markets (Level 1)Significant Other Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Environmental Settlement Obligations$6,400 $6,270 $— $— $6,270 
Total acquisition-related obligations$6,400 $6,270 $— $— $6,270 

 December 31, 2020
Carrying
Amount (1)
Total Fair ValueQuoted Prices in Active Markets (Level 1)Significant Other Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
UMWA Funds Settlement Liability$1,662 $1,426 $— $— $1,426 
Environmental Settlement Obligations9,237 7,760 — — 7,760 
Total acquisition-related obligations$10,899 $9,186 $— $— $9,186 
(1) Net of discounts.
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis The following table sets forth by level, within the fair value hierarchy, the Company’s financial and non-financial assets and liabilities that were accounted for at fair value on a recurring basis as of December 31, 2021 and 2020. Financial and non-financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement requires judgment, and may affect the determination of fair value for assets and liabilities and their placement within the fair value hierarchy levels.
 December 31, 2021
Total Fair ValueQuoted Prices in Active Markets (Level 1)Significant Other Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Contingent Revenue Obligation$35,005 $— $— $35,005 
Trading securities$28,443 $27,075 $1,368 $— 
 December 31, 2020
Total Fair ValueQuoted Prices in Active Markets (Level 1)Significant Other Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Contingent Revenue Obligation$28,967 $— $— $28,967 
Trading securities$22,498 $20,092 $2,406 $— 

The following table is a reconciliation of the financial and non-financial assets and liabilities that were accounted for at fair value on a recurring basis and that were categorized within Level 3 of the fair value hierarchy:
December 31, 2020PaymentsLoss Recognized in EarningsTransfer In (Out) of Level 3 Fair Value HierarchyDecember 31, 2021
Contingent Revenue Obligation $28,967 $(13,487)$19,525 $— $35,005 
(1) The loss recognized in earnings resulted primarily from an increase in forecasted future revenue as of December 31, 2021.

December 31, 2019PaymentsGain Recognized in EarningsTransfer In (Out) of Level 3 Fair Value HierarchyDecember 31, 2020
Contingent Revenue Obligation$52,427 $(14,710)$(8,750)$— $28,967 
(1) The gain recognized in earnings resulted primarily from a change in the forecasted future revenue associated with this obligation and an increase in annualized volatility as of December 31, 2020.
Range of Significant Unobservable Inputs The range of significant unobservable inputs used to value the Contingent Revenue Obligation as of December 31, 2021 and 2020 are set forth in the following table:
 December 31, 2021December 31, 2020
Forecasted future revenue
$1.5 - $2.0 billion
$0.9 - $1.1 billion
Stated royalty rate
1.0% - 1.5%
1.0% - 1.5%
Annualized volatility
18.4% - 39.3% (29.9%)
19.4% - 52.1% (28.0%)
v3.22.0.1
Income Taxes (Tables)
 12 Months Ended
Dec. 31, 2021
Income Tax Disclosure [Abstract]  
Schedule of Allocation of Income Tax Expense (Benefit)
Total income tax expense (benefit) provided on income (loss) before income taxes was allocated as follows:
Year Ended December 31,
20212020
Continuing operations$3,609 $(2,164)
Discontinued operations(201)— 
Total$3,408 $(2,164)
Schedule of Components of Income Tax Expense (Benefit) Significant components of income tax expense (benefit) from continuing operations were as follows:
Year Ended December 31,
20212020
Current tax expense (benefit):
Federal$2,586 $(35,187)
State1,186 (99)
Total current$3,772 $(35,286)
Deferred tax (benefit) expense:
Federal$(3)$33,348 
State(160)(226)
Total deferred $(163)$33,122 
Total income tax expense (benefit):
Federal$2,583 $(1,839)
State1,026 (325)
Total$3,609 $(2,164)
Schedule of Effective Income Tax Rate Reconciliation
A reconciliation of statutory federal income tax expense (benefit) on income (loss) from continuing operations to the actual income tax expense (benefit) is as follows:
Year Ended December 31,
20212020
Federal statutory income tax expense (benefit)$61,013 $(51,163)
Increase (reductions) in taxes due to:
Percentage depletion allowance(11,864)(2,039)
AMT sequestration refund— (2,123)
State taxes, net of federal tax impact12,998 (9,640)
State apportioned tax rate change, net of federal tax impact8,751 (1,235)
Change in valuation allowances(78,056)59,929 
Capital loss expiration10,552 — 
Stock-based compensation405 1,739 
Other, net (190)2,368 
Income tax expense (benefit)$3,609 $(2,164)
Schedule of Deferred Tax Assets and Liabilities The net deferred tax assets and liabilities included in the Consolidated Balance Sheets include the following amounts:
Year Ended December 31,
20212020
Deferred tax assets:
  Asset retirement obligations$36,252 $41,268 
  Reserves and accruals not currently deductible9,610 12,131 
  Workers’ compensation benefit obligations47,105 59,478 
Pension obligations34,956 52,598 
  Equity method investments1,846 2,050 
Loss carryforwards, net of Section 382 limitation187,341 255,772 
  Acquisition-related obligations9,156 10,002 
  Other 7,100 10,976 
     Gross deferred tax assets333,366 444,275 
Less valuation allowance(172,883)(263,387)
     Deferred tax assets$160,483 $180,888 
Deferred tax liabilities:
Property, plant and mineral reserves$(134,075)$(141,549)
  Acquired intangibles, net(16,408)(22,037)
  Prepaid expenses(4,955)(6,211)
Restricted cash(5,362)(11,516)
  Other — (55)
     Total deferred tax liabilities(160,800)(181,368)
     Net deferred tax liabilities$(317)$(480)
Summary of Valuation Allowance
Changes in the valuation allowance were as follows:
Year Ended December 31,
20212020
Valuation allowance beginning of period$263,387 $133,020 
(Decrease) increase in valuation allowance recorded to income tax expense (benefit) (78,043)117,829 
(Decrease) increase in valuation allowance not affecting income tax expense (benefit)(12,461)12,538 
Valuation allowance end of period$172,883 $263,387 
Schedule of Liability for Uncertain Tax Positions
The following reconciliation illustrates the Company’s liability for uncertain tax positions:
Year Ended December 31,
20212020
Unrecognized tax benefits - beginning of period$— $20,788 
Reductions for tax positions of prior years— (20,788)
Unrecognized tax benefits - end of period$— $— 
v3.22.0.1
Employee Benefit Plans (Tables)
 12 Months Ended
Dec. 31, 2021
Compensation Related Costs [Abstract]  
Changes in Accumulated Benefits Obligations, Fair Value of Plan Assets and Funded Status of Plan
The following tables set forth the Pension Plans’ accumulated benefit obligations, fair value of plan assets and funded status for the years ended December 31, 2021 and 2020.
Year Ended December 31,
20212020
Change in benefit obligations:
Accumulated benefit obligation at beginning of period:$723,448 $674,439 
Interest cost 13,566 18,730 
Actuarial (gain) loss (1)
(34,922)72,822 
Benefits paid(30,222)(30,916)
Settlement(3,815)(11,627)
Accumulated benefit obligation at end of period$668,055 $723,448 
Change in fair value of plan assets:
Fair value of plan assets at beginning of period$504,777 $470,353 
Actual return on plan assets30,814 54,222 
Employer contributions6,571 22,745 
Benefits paid(30,222)(30,916)
Settlement(3,815)(11,627)
Fair value of plan assets at end of period$508,125 $504,777 
Funded status$(159,930)$(218,671)
Accrued benefit cost at end of period (2)
$(159,930)$(218,671)
(1) For the years ended December 31, 2021 and 2020, the actuarial (gain) loss was primarily attributable to the change in the weighted-average discount rate actuarial assumption used in determining the benefit obligations.
(2) Amounts are classified as long-term on the Consolidated Balance Sheets as there are sufficient plan assets to make expected benefit payments to plan participants in the succeeding twelve months.
The following tables set forth the accumulated black lung benefit obligations, fair value of plan assets and funded status for the years ended December 31, 2021 and 2020:
Year Ended December 31,
20212020
Change in benefit obligation:
Accumulated benefit obligation at beginning of period$127,506 $122,788 
Service cost2,972 2,361 
Interest cost2,463 3,240 
Actuarial (gain) loss (1)
(9,759)14,736 
Benefits paid(6,040)(7,166)
Curtailment gain— (163)
Settlement— (8,290)
Accumulated benefit obligation at end of period$117,142 $127,506 
Change in fair value of plan assets:
Fair value of plan assets at beginning of period$2,720 $2,660 
Actual return on plan assets(56)60 
Benefits paid(6,040)(7,166)
Employer contributions6,040 7,166 
Fair value of plan assets at end of period (2)
2,664 2,720 
Funded status$(114,478)$(124,786)
Accrued benefit cost at end of period$(114,478)$(124,786)
Summary of accrued benefit cost at end of period:
Continuing operations(111,854)(122,961)
Discontinued operations (3)
(2,624)(1,825)
Total accrued benefit cost at end of period$(114,478)$(124,786)
(1) For the years ended December 31, 2021 and 2020, the actuarial (gain) loss was primarily attributable to the change in the weighted-average discount rate actuarial assumption used in determining the benefit obligations.
(2) Assets of the plan are held in a Section 501(c)(21) tax-exempt trust fund and consist primarily of government debt securities. All assets are classified as Level 1 and valued based on quoted market prices.
(3) The discontinued operations consisted of activity related to the Company’s former NAPP operations. Refer to Note 3
Schedule of Amounts Recognized in Accumulated Other Comprehensive (Income) Loss Gross amounts related to benefit obligations recognized in accumulated other comprehensive loss consisted of the following as of December 31, 2021 and 2020:
December 31,
20212020
Net actuarial loss$47,950 $88,583 
Gross amounts related to the black lung benefit obligations recognized in accumulated other comprehensive loss consisted of the following as of December 31, 2021 and 2020: 
December 31,
20212020
Net actuarial loss $11,940 $24,042 
Schedule of Net Periodic Benefit Cost
The following table details the components of net periodic benefit credit:
Year Ended December 31,
20212020
Interest cost$13,566 $18,730 
Expected return on plan assets(28,732)(27,064)
Amortization of net actuarial loss3,217 2,012 
Settlement412 1,636 
Net periodic benefit credit$(11,537)$(4,686)
The following table details the components of the net periodic benefit cost for the black lung benefit obligations:
Year Ended December 31,
20212020
Service cost$2,972 $2,361 
Interest cost2,463 3,240 
Expected return on plan assets(54)(54)
Amortization of net actuarial loss 2,453 1,942 
Settlement— 1,563 
Net periodic benefit cost$7,834 $9,052 
Summary net periodic benefit cost:
Continuing operations$7,418 $7,670 
Discontinued operations (1)
416 1,382 
Total net periodic benefit cost$7,834 $9,052 
(1) The discontinued operations consisted of activity related to the Company’s former NAPP operations. Refer to Note 3.
Schedule of Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive (Income) Loss
Other changes in plan assets and benefit obligations recognized in other comprehensive income (loss) are as follows:
Year Ended December 31,
20212020
Actuarial (gain) loss$(37,004)$45,663 
Amortization of net actuarial loss(3,217)(2,012)
Settlement(412)(1,636)
Total recognized in other comprehensive income (loss)$(40,633)$42,015 
Other changes in the black lung plan assets and benefit obligations recognized in other comprehensive income (loss) are as follows:
Year Ended December 31,
20212020
Actuarial (gain) loss$(9,649)$14,567 
Amortization of net actuarial loss(2,453)(1,942)
Settlement— (1,563)
Total recognized in other comprehensive income (loss)$(12,102)$11,062 
Schedule of Benefit Obligations in Excess of Fair Value of Plan Assets
The following table presents information applicable to plans with accumulated benefit obligations in excess of plan assets:
Year Ended December 31,
20212020
Projected benefit obligation$668,055 $723,448 
Accumulated benefit obligation$668,055 $723,448 
Fair value of plan assets$508,125 $504,777 
Schedule of Assumptions Used
The weighted-average actuarial assumption used in determining the benefit obligations as of December 31, 2021 and 2020 was as follows: 
December 31,
20212020
Discount rate2.92 %2.62 %

The weighted-average actuarial assumptions used to determine net periodic benefit credit for the years ended December 31, 2021 and 2020 were as follows: 
Year Ended December 31,
20212020
Discount rate for benefit obligation2.62 %3.35 %
Discount rate for interest cost1.96 %2.92 %
Expected long-term rate of return on plan assets5.80 %5.90 %
The weighted-average assumptions related to black lung obligations used to determine the benefit obligation as of December 31, 2021 and 2020 were as follows: 
December 31,
20212020
Discount rate2.96 %2.75 %
Federal black lung income benefit trend rate2.00 %2.00 %
Federal black lung medical benefit trend rate5.00 %5.00 %
Black lung benefit expense inflation rate (1)
— %2.00 %
(1) Effective in 2021, the annual claim administration expenses are incorporated into the annual service cost component of the net periodic benefit cost for the black lung benefit obligations.

The weighted-average assumptions related to black lung benefit obligations used to determine net periodic benefit cost were as follows:
Year Ended December 31,
20212020
Discount rate for benefit obligation2.75 %3.47 %
Discount rate for service cost3.15 %3.56 %
Discount rate for interest cost1.96 %2.61 %
Federal black lung income benefit trend rate2.00 %2.50 %
Federal black lung medical benefit trend rate5.00 %5.00 %
Black lung benefit expense inflation rate (1)
— %2.00 %
Expected return on plan assets2.00 %2.00 %
(1) Effective in 2021, the annual claim administration expenses are incorporated into the annual service cost component of the net periodic benefit cost for the black lung benefit obligations.
Schedule of Allocation of Plan Assets The target allocation for 2022 and the actual asset allocation as reported at December 31, 2021 are as follows:
Target Allocation Percentages 2022 (1)
Percentage of Plan Assets 2021
Equity securities60.0 %56.0 %
Fixed income funds40.0 %41.0 %
Other— %3.0 %
Total100.0 %100.0 %
(1) Assumes the Pension Plans have a funded status level less than 90.0%.
Schedule of Estimated Cash Payments
The following represents expected future pension benefit payments for the next ten years:
2022$30,949 
202330,944 
202431,161 
202531,497 
202631,657 
2027-2031158,207 
$314,415 
Estimated future cash payments related to black lung benefit obligations for the next 10 years ending after December 31, 2021 are as follows: 
Year ending December 31:
2022$7,295 
20237,208 
20247,254 
20257,329 
20267,497 
2027-203119,889 
$56,472 
Schedule of Changes in Fair Value of Plan Assets The fair values of the Company’s Pension Plans’ assets as of December 31, 2021, by asset category are as follows:
Asset CategoryTotalQuoted Market Prices in Active Market for Identical Assets (Level 1)Significant Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Equity securities:
Multi-asset fund (1)
$284,568 $— $284,568 $— 
Fixed income funds:
Bond fund (2)
208,466 — 208,466 — 
Commingled short-term fund (3)
1,384 — 1,384 — 
Other types of investments:
Guaranteed insurance contract11,652 — — 11,652 
Total$506,070 $— $494,418 $11,652 
Receivable (4)
876 
Total assets at fair value506,946 
Private equity funds measured at net asset value practical expedient (5)
1,179 
Total plan assets$508,125 
(1) This fund contains equities (domestic and international), real estate and bonds.
(2) This fund contains bonds representing a diversity of sectors and maturities. This fund also includes mortgage-backed securities and U.S. Treasuries.
(3) This fund contains cash and highly liquid short-term investments in a collective investment fund.
(4) Receivable for investments sold at December 31, 2021, which approximates fair value.
(5) In accordance with Accounting Standards Update 2015-07, investments that are measured at fair value using the net asset value per share practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the total value of assets of the plans.

Changes in Level 3 plan assets for the period ended December 31, 2021 were as follows:
Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
Guaranteed Insurance Contract
Beginning balance, December 31, 2020$11,454 
Actual return on plan assets:
Relating to assets still held at the reporting date528 
Purchases, sales and settlements(330)
Ending balance, December 31, 2021$11,652 

The fair values of the Company’s Pension Plans’ assets as of December 31, 2020, by asset category are as follows:
Asset CategoryTotalQuoted Market Prices in Active Market for Identical Assets (Level 1)Significant Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Equity securities:
Multi-asset fund (1)
$236,405 $— $236,405 $— 
Fixed income funds:
Bond fund (2)
253,218 — 253,218 — 
Commingled short-term fund (3)
1,405 — 1,405 — 
Other types of investments:
Guaranteed insurance contract11,454 — — 11,454 
Total$502,482 $— $491,028 $11,454 
Receivable (4)
888 
Total assets at fair value503,370 
Private equity funds measured at net asset value practical expedient (5)
1,407 
Total plan assets$504,777 
(1) This fund contains equities (domestic and international), real estate and bonds.
(2) This fund contains bonds representing a diversity of sectors and maturities. This fund also includes mortgage-backed securities and U.S. Treasuries.
(3) This fund contains cash and highly liquid short-term investments in a collective investment fund.
(4) Receivable for investments sold at December 31, 2020, which approximates fair value.
(5) In accordance with Accounting Standards Update 2015-07, investments that are measured at fair value using the net asset value per share practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the total value of assets of the plans.

Changes in Level 3 plan assets for the period ended December 31, 2020 were as follows:
Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
Guaranteed Insurance Contract
Beginning balance, December 31, 2019$11,155 
Actual return on plan assets:
Relating to assets still held at the reporting date659 
Purchases, sales and settlements(360)
Ending balance, December 31, 2020$11,454 
Schedule of Workers' Compensation
The table below presents workers’ compensation amounts recognized in the Consolidated Balance Sheets:
December 31,
20212020
Current liabilities$10,582 $10,355 
Current liabilities - discontinued operations (1)
2,730 4,847 
Long-term liabilities103,574 113,904 
Long-term liabilities - discontinued operations (1)
21,119 26,000 
Total liabilities$138,005 $155,106 
Less expected insurance receivable (2)
(47,644)(50,688)
Less long-term expected insurance receivable - discontinued operations (1)
(6,020)(6,970)
Workers’ compensation obligations, net of expected insurance receivables$84,341 $97,448 
(1) The discontinued operations consisted of activity related to the Company’s former NAPP operations. Refer to Note 3.
(2) Included within Prepaid expenses and other current assets and Other non-current assets in the Consolidated Balance Sheets.
Schedule of Amounts Recognized in Balance Sheet The table below presents amounts recognized in the Consolidated Balance Sheets:
December 31,
20212020
Current liabilities$7,235 $6,784 
Current liabilities - discontinued operations60 26 
Long-term liabilities104,619 116,177 
Long-term liabilities - discontinued operations2,564 1,799 
Total liabilities$114,478 $124,786 
v3.22.0.1
Stock-Based Compensation Awards (Tables)
 12 Months Ended
Dec. 31, 2021
Share-based Payment Arrangement [Abstract]  
Schedule of Valuation Assumptions The Monte Carlo simulation incorporated the assumptions as presented in the following table:
Relative performance-based restricted stock units
Start price (1)
$11.81 
Valuation date stock price (2)
$11.34 
Expected volatility (3)
98.54 %
Risk-free interest rate (4)
0.18 %
Expected dividend yield (5)
— %
(1)    The start price for the Company represented the average closing stock price over the twenty trading days ending on December 31, 2020, assuming dividends distributed during this period were reinvested in additional shares of the Company’s stock on the ex-dividend date.
(2)    The valuation date stock price represented the closing price on the grant date.
(3)    The expected volatility assumption was based on the historical volatility of the price of the Company’s stock.
(4)    The annual risk-free interest rate equaled the yield on the semi-annual zero coupon U.S. Treasury rates converted to continuously compounded rates that had a term equal to the length of the remaining performance measurement period as of the valuation date.
(5)    The expected dividend yield represented the investments return to a share of the Company’s stock that is not available to the holder of the performance-based restricted stock unit.
The Monte Carlo simulation incorporates the assumptions as presented in the following table:
Performance-based cash incentive awards
Start price (1)
$11.81 
Valuation date stock price (2)
$11.34 
Expected volatility (3)
98.54 %
Risk-free interest rate (4)
0.18 %
Expected dividend yield (5)
— %
(1)    The start price for the Company represents the average closing stock price over the twenty trading days ending on December 31, 2020, assuming dividends distributed during this period were reinvested in additional shares of the Company’s stock on the ex-dividend date.
(2)    The valuation date stock price represents the closing price at each reporting date.
(3)    The expected volatility assumption is based on the historical volatility of the price of the Company’s stock.
(4)    The annual risk-free interest rate equals the yield on the semi-annual zero coupon U.S. Treasury rates converted to continuously compounded rates that have a term equal to the length of the remaining performance measurement period as of the valuation date.
(5)    The expected dividend yield represents the investments return to a share of the Company’s stock that is not available to the holder of the performance-based restricted stock unit.
The Monte Carlo simulation incorporated the assumptions as presented in the following table:
Relative performance-based restricted stock units
Start price (1)
$7.59 
Valuation date stock price (2)
$6.33 
Expected volatility (3)
55.27 %
Risk-free interest rate (4)
1.37 %
Expected dividend yield (5)
— %
(1)    The start price for the Company represented the average closing stock price over the twenty trading days ending on December 31, 2019, assuming dividends distributed during this period were reinvested in additional shares of the Company’s stock on the ex-dividend date.
(2)    The valuation date stock price represented the closing price on the grant date.
(3)    The expected volatility assumption was based on the historical volatility of the price of the Company’s stock.
(4)    The annual risk-free interest rate equaled the yield on the semi-annual zero coupon U.S. Treasury rates converted to continuously compounded rates that had a term equal to the length of the remaining performance measurement period as of the valuation date.
(5)    The expected dividend yield represented the investments return to a share of the Company’s stock that is not available to the holder of the performance-based restricted stock unit.
The Monte Carlo simulation incorporates the assumptions as presented in the following table:
Performance-based cash incentive awards
Start price (1)
$7.59 
Valuation date stock price (2)
$6.33 
Expected volatility (3)
55.27 %
Risk-free interest rate (4)
1.37 %
Expected dividend yield (5)
— %
(1)    The start price for the Company represents the average closing stock price over the twenty trading days ending on December 31, 2019, assuming dividends distributed during this period were reinvested in additional shares of the Company’s stock on the ex-dividend date.
(2)    The valuation date stock price represents the closing price at each reporting date.
(3)    The expected volatility assumption is based on the historical volatility of the price of the Company’s stock.
(4)    The annual risk-free interest rate equals the yield on the semi-annual zero coupon U.S. Treasury rates converted to continuously compounded rates that have a term equal to the length of the remaining performance measurement period as of the valuation date.
(5)    The expected dividend yield represents the investments return to a share of the Company’s stock that is not available to the holder of the performance-based restricted stock unit.
Schedule of Restricted Stock Shares and Restricted Share Units Activity
Time-based restricted stock unit activity for the year ended December 31, 2021 is summarized in the following table: 
Time-based restricted stock unit activity:Number of  SharesWeighted-Average Grant  Date Fair Value
Non-vested shares outstanding at December 31, 2020367,553 $13.72 
Granted223,496 $12.03 
Vested (1)
(193,854)$16.05 
Forfeited(4,920)$19.22 
Non-vested shares outstanding at December 31, 2021392,275 $11.54 
(1) Includes 61,646 shares with deferred settlement pursuant to the award agreements.
Schedule of Performance Shares Activity
Relative performance-based restricted stock unit activity for the year ended December 31, 2021 based on target achievement of the performance criteria is summarized in the following table: 
Relative performance-based restricted stock unit activity:Number of  SharesWeighted-Average Grant  Date Fair Value
Non-vested shares outstanding at December 31, 2020174,203 $16.01 
Granted67,035 $16.18 
Vested— $— 
Forfeited or Cancelled(153,016)$9.13 
Non-vested shares outstanding at December 31, 2021 (1)
88,222 $28.07 
(1) During the first quarter of 2022, 46,551 shares were cancelled and allocated back to the LTIP for future issuance as the 2019 award’s performance metric was not achieved.
Absolute performance-based restricted stock unit activity for the year ended December 31, 2021 based on target achievement of the performance criteria is summarized in the following table: 
Absolute performance-based restricted stock unit activity:Number of SharesWeighted-Average Grant  Date Fair Value
Non-vested shares outstanding at December 31, 20207,614 $50.60 
Granted— $— 
Vested— $— 
Forfeited(541)$50.60 
Non-vested shares outstanding at December 31, 2021 (1)
7,073 $50.60 
(1) During the first quarter of 2022, 15,532 shares were cancelled and allocated back to the LTIP for future issuance as the 2019 award’s performance metric was not achieved.
Operational performance-based restricted stock unit activity for the year ended December 31, 2021 based on target achievement of the performance criteria is summarized in the following table: 
Operational performance-based restricted stock unit activity:
Number of  SharesWeighted-Average Fair Value
Non-vested shares outstanding at December 31, 2020151,398 $6.36 
Granted100,552 $12.00 
Vested— $— 
Cancelled(151,398)$6.36 
Non-vested shares outstanding at December 31, 2021100,552 $12.00 
Performance-based cash incentive award activity for the year ended December 31, 2021 based on target achievement of the performance criteria is summarized in the following table: 
Performance-based cash incentive award activity:Target Dollar ValueWeighted-Average Fair Value as a % of Target Dollar Value
Non-vested awards outstanding at December 31, 2020$2,206 94.21 %
Granted927 51.73 %
Vested— — %
Forfeited(142)78.45 %
Non-vested awards outstanding at December 31, 2021$2,991 162.03 %
Schedule of Stock Option Activity
30-day VWAP stock option activity for the year ended December 31, 2021 is summarized in the following table:
Number of SharesWeighted-Average Exercise Price Per ShareWeighted-Average Remaining Contractual Term (Years)
Aggregate Intrinsic Value (1)
Outstanding at December 31, 202023,225 $60.20 6.12$(1,134)
Exercisable at December 31, 202023,225 $60.20 6.12$(1,134)
Granted— $— 
Exercised— $— $— 
Forfeited or Expired— $— 
Outstanding at December 31, 202123,225 $60.20 5.12$20 
Exercisable at December 31, 202123,225 $60.20 5.12$20 
(1) The aggregate intrinsic value of outstanding and exercisable options is calculated as the difference between the exercise price and the Company’s stock price at each reporting period end. The aggregate intrinsic value of exercised options is calculated as the difference between the exercise price and the Company’s stock price on the exercise date.
v3.22.0.1
Commitment and Contingencies (Tables)
 12 Months Ended
Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]  
Restrictions on Cash and Cash Equivalents
Amounts included in restricted cash represent cash deposits primarily invested in interest-bearing accounts that are restricted as to withdrawal as required by certain agreements entered into by the Company and provide collateral to secure the following obligations which have been written on the Company’s behalf:

December 31, 2021December 31, 2020
Workers’ compensation and black lung obligations$70,637 $69,725 
Reclamation-related obligations10,449 8,445 
Financial payments and other performance obligations8,340 17,863 
Contingent Revenue Obligation escrow11,977 9,311 
Total restricted cash101,403 105,344 
Less current portion (1)
(11,977)(9,311)
Restricted cash, net of current portion$89,426 $96,033 
(1) Included within Prepaid expenses and other current assets on the Company’s Consolidated Balance Sheets.
Prepaid Expenses and Other Current Assets
Prepaid expenses and other current assets consisted of the following:
December 31,
 20212020
Prepaid freight$19,671 $8,515 
Notes and other receivables4,161 13,245 
Short-term restricted cash11,977 9,311 
Prepaid insurance8,525 6,510 
Refundable income taxes— 64,565 
Prepaid bond premium1,649 2,576 
Other prepaid expenses1,707 1,530 
Total prepaid expenses and other current assets$47,690 $106,252 
Restricted investments consist of FDIC insured certificates of deposit, mutual funds, and U.S. treasury bills that are restricted as to withdrawal as required by certain agreements entered into by the Company and provide collateral to secure the following obligations which have been written on the Company’s behalf:

December 31, 2021December 31, 2020
Workers’ compensation obligations$210 $51 
Reclamation-related obligations26,225 22,233 
Financial payments and other performance obligations2,008 1,484 
Total restricted investments (1), (2)
$28,443 $23,768 
(1) Included within Other non-current assets on the Company’s Consolidated Balance Sheets.
(2) As of December 31, 2021 and 2020, respectively, $28,443 and $22,498 are classified as trading securities and $0 and $1,270 are classified as held-to-maturity securities.
Deposits represent cash deposits held at third parties as required by certain agreements entered into by the Company to provide cash collateral to secure the following obligations which have been written on the Company’s behalf:
December 31, 2021December 31, 2020
Reclamation-related obligations$118 $25,633 
Financial payments and other performance obligations403 1,596 
Other operating agreements873 1,018 
Total deposits (1)
$1,394 $28,247 
(1) Included within Prepaid expenses and other current assets and other non-current assets on the Company’s Consolidated Balance Sheets.
v3.22.0.1
Concentration of Credit Risk and Major Customers (Tables)
 12 Months Ended
Dec. 31, 2021
Risks and Uncertainties [Abstract]  
Schedule of Concentration of Credit Risk and Major Customers The following table presents additional information on our total revenues and top customers:
Year Ended December 31,
 20212020
Total revenue$2,258,586 $1,416,187 
Top customer as % of total revenue 13 %16 %
Top 10 customers as % of total revenue 64 %63 %
Number of customers exceeding 10% of total revenue2 2 
Number of customers exceeding 10% of total trade accounts receivable, net3 3 
Domestic revenue as % of coal revenue 24 %36 %
Export revenue as % of coal revenue 76 %64 %
Countries with export revenue exceeding 10% of total revenue India, China, BrazilIndia, Brazil
Met coal as % of coal sales volume83 %80 %
Thermal coal as % of coal sales volume17 %20 %
v3.22.0.1
Segment Information (Tables)
 12 Months Ended
Dec. 31, 2021
Segment Reporting [Abstract]  
Schedule of Segment Operating Results and Capital Expenditures
Segment operating results and capital expenditures from continuing operations for the year ended December 31, 2021 were as follows: 
Year Ended December 31, 2021
MetAll OtherConsolidated
Total revenues$2,176,080 $82,506 $2,258,586 
Depreciation, depletion, and amortization$99,963 $10,084 $110,047 
Amortization of acquired intangibles, net$13,671 $(427)$13,244 
Adjusted EBITDA$567,270 $(34,447)$532,823 
Capital expenditures$79,185 $4,115 $83,300 
Segment operating results and capital expenditures from continuing operations for the year ended December 31, 2020 were as follows: 
Year Ended December 31, 2020
MetAll OtherConsolidated
Total revenues$1,264,496 $151,691 $1,416,187 
Depreciation, depletion, and amortization$124,060 $15,825 $139,885 
Amortization of acquired intangibles, net$12,889 $(3,675)$9,214 
Adjusted EBITDA$120,281 $(36,880)$83,401 
Capital expenditures$111,745 $7,834 $119,579 
Reconciliation of Net Income (Loss) to Adjusted EBITDA
The following table presents a reconciliation of net income (loss) from continuing operations to Adjusted EBITDA for the year ended December 31, 2021:
Year Ended December 31, 2021
MetAll OtherConsolidated
Net income (loss) from continuing operations$439,859 $(152,930)$286,929 
Interest expense184 69,470 69,654 
Interest income(6)(328)(334)
Income tax expense— 3,609 3,609 
Depreciation, depletion and amortization99,963 10,084 110,047 
Non-cash stock compensation expense28 5,287 5,315 
Mark-to-market adjustment - acquisition-related obligations— 19,525 19,525 
Gain on settlement of acquisition-related obligations— (1,125)(1,125)
Accretion on asset retirement obligations13,571 12,949 26,520 
Asset impairment and restructuring — (561)(561)
Amortization of acquired intangibles, net13,671 (427)13,244 
Adjusted EBITDA $567,270 $(34,447)$532,823 
The following table presents a reconciliation of net loss from continuing operations to Adjusted EBITDA for the year ended December 31, 2020:
Year Ended December 31, 2020
MetAll OtherConsolidated
Net loss from continuing operations$(77,519)$(163,951)$(241,470)
Interest expense(2,014)76,542 74,528 
Interest income(63)(6,964)(7,027)
Income tax benefit— (2,164)(2,164)
Depreciation, depletion and amortization124,060 15,825 139,885 
Non-cash stock compensation expense289 4,607 4,896 
Mark-to-market adjustment - acquisition-related obligations— (8,750)(8,750)
Accretion on asset retirement obligations14,214 12,290 26,504 
Asset impairment and restructuring 46,317 37,561 83,878 
Management restructuring costs (1)
501 440 941 
Loss on partial settlement of benefit obligations1,607 1,359 2,966 
Amortization of acquired intangibles, net12,889 (3,675)9,214 
Adjusted EBITDA $120,281 $(36,880)$83,401 
(1) Management restructuring costs are related to severance expense associated with senior management changes during the three months ended March 31, 2020.
v3.22.0.1
Summary of Significant Accounting Policies - Property, Plant, and Equipment, Net (Details) - Mining equipment, buildings and other fixed assets
 12 Months Ended
Dec. 31, 2021
Minimum  
Property, Plant and Equipment [Line Items]  
Property, plant and equipment, useful lives 1 year
Maximum  
Property, Plant and Equipment [Line Items]  
Property, plant and equipment, useful lives 25 years
v3.22.0.1
Summary of Significant Accounting Policies - Owned and Leased Mineral Rights (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2020
Sep. 30, 2020
Jun. 30, 2020
Mar. 31, 2020
Dec. 31, 2021
Dec. 31, 2020
Property, Plant and Equipment [Line Items]            
Owned and leased mineral rights $ 463,250       $ 444,302 $ 463,250
Asset retirement obligation assets 10,491       10,354 10,491
Impairment of long-lived assets 29,636 $ 219 $ 17,390 $ 33,709   80,954
Depletion         23,541 (13,746)
Revisions in estimated cash flows         (12,744) (43,765)
Mineral rights, net            
Property, Plant and Equipment [Line Items]            
Impairment of long-lived assets $ 17,513 $ 0 $ 2,241 $ 21,825   41,579
Revisions in estimated cash flows         $ 5,782 $ (34,377)
v3.22.0.1
Summary of Significant Accounting Policies - Acquired Intangible Assets and Liabilities (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2020
Sep. 30, 2020
Jun. 30, 2020
Mar. 31, 2020
Dec. 31, 2020
Dec. 31, 2021
Finite-Lived Intangible Assets [Line Items]            
Assets $ 88,196       $ 88,196 $ 74,197
Liabilities (327)       (327) 0
Assets, net 87,869       87,869 74,197
Impairment of long-lived assets 29,636 $ 219 $ 17,390 $ 33,709 80,954  
Mine permits            
Finite-Lived Intangible Assets [Line Items]            
Impairment of long-lived assets 6,673 $ 0 $ 8,653 $ 5,818 21,144  
Coal supply agreements, net            
Finite-Lived Intangible Assets [Line Items]            
Liabilities (327)       (327) 0
Liabilities, net (327)       (327) 0
Mine permits            
Finite-Lived Intangible Assets [Line Items]            
Liabilities 0       0 0
Coal supply agreements, net            
Finite-Lived Intangible Assets [Line Items]            
Assets 0       0 0
Assets, net           74,197
Mine permits            
Finite-Lived Intangible Assets [Line Items]            
Assets 88,196       88,196 $ 74,197
Assets, net $ 88,196       $ 88,196  
v3.22.0.1
Summary of Significant Accounting Policies - Amortization of Intangible Assets and Liabilities (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]    
Amortization of intangible assets $ 13,244 $ 9,214
Mine permits    
Finite-Lived Intangible Assets [Line Items]    
Amortization of intangible assets 13,571 14,887
Coal supply agreements    
Finite-Lived Intangible Assets [Line Items]    
Amortization of intangible assets 0 18
Amortization of intangible liabilities (327) (5,691)
Amortization of acquired intangibles, net $ (327) $ (5,673)
v3.22.0.1
Summary of Significant Accounting Policies - Future Amortization Expense of Acquired Intangibles (Details) - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Accounting Policies [Abstract]    
2022 $ 11,749  
2023 8,079  
2024 6,728  
2025 6,723  
2026 6,196  
Thereafter 34,722  
Total net future amortization expense $ 74,197 $ 87,869
v3.22.0.1
Summary of Significant Accounting Policies - Workers' Compensation (Details) - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Accounting Policies [Abstract]    
Worker's compensation discount $ 23,442 $ 24,061
v3.22.0.1
Summary of Significant Accounting Policies - Warrants (Details) - $ / shares
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Jul. 26, 2016
Accounting Policies [Abstract]      
Number of warrants outstanding (in shares) 801,246 801,370 810,811
Exercise price of warrants (in dollars per share) $ 46.911 $ 46.911 $ 55.93
Number of securities called by each warrant (in shares) 1.15 1.15 1
Common stock, par value (in dollars per share) $ 0.01 $ 0.01 $ 0.01
Number of securities called by outstanding warrants (in shares) 921,433 921,576  
Shares issued upon exercise of warrants (in shares) 143    
Shares withheld upon exercise of warrants (in shares) 17    
v3.22.0.1
Summary of Significant Accounting Policies - Equity Method Investments (Details) - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Accounting Policies [Abstract]    
Equity method investments $ 20,460 $ 18,383
v3.22.0.1
Summary of Significant Accounting Policies - Recently Adopted Accounting Guidance (Details) - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Jan. 01, 2020
Dec. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]        
Total stockholders’ equity $ 546,909 $ 200,102   $ 696,122
Retained Earnings (Accumulated Deficit)        
New Accounting Pronouncements or Change in Accounting Principle [Line Items]        
Total stockholders’ equity $ (71,739) $ (360,529)   86,810
Cumulative Effect, Period of Adoption, Adjustment        
New Accounting Pronouncements or Change in Accounting Principle [Line Items]        
Total stockholders’ equity       (440)
Cumulative Effect, Period of Adoption, Adjustment | Retained Earnings (Accumulated Deficit)        
New Accounting Pronouncements or Change in Accounting Principle [Line Items]        
Total stockholders’ equity     $ (440) $ (440)
v3.22.0.1
Discontinued Operations - Narrative (Details)
T in Thousands, $ in Thousands
 12 Months Ended
Dec. 31, 2022
USD ($)
T
Dec. 31, 2021
USD ($)
T
Dec. 31, 2020
USD ($)
T
Guarantor Obligations [Line Items]      
Income (loss) from discontinued operations before income taxes   $ 1,660 $ (205,429)
Cumberland Back-to-Back Coal Supply Agreement      
Guarantor Obligations [Line Items]      
Purchased and sold, tons | T   2,591 104
Purchased and sold   $ 100,338 $ 3,997
Cumberland Back-to-Back Coal Supply Agreement | Forecast      
Guarantor Obligations [Line Items]      
Purchased and sold, tons | T 2,014    
Purchased and sold $ 77,844    
Discontinued Operations, Disposed of by Sale | Cumberland Transaction      
Guarantor Obligations [Line Items]      
Consideration     $ 49,987
Remaining surety bond and expected to be released in short-term   $ 30  
v3.22.0.1
Discontinued Operations - Cumberland Transaction (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]    
Cash $ 0 $ 52,192
Loss on sale $ 0 36,113
Cumberland Transaction | Discontinued Operations, Disposed of by Sale    
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]    
Cash   19,987
Surety bonding collateral   30,000
Total consideration   49,987
Transaction costs   2,205
Carrying value of transferred assets and liabilities   (16,079)
Loss on sale   36,113
Property, plant and equipment, net   32,872
Deferred longwall move expenses   15,173
Coal and supplies inventory   5,112
Asset retirement obligations assumed   39,573
Severance   17,143
Black lung obligations   8,290
Subsidence liability   $ 3,559
v3.22.0.1
Discontinued Operations - Major Components of Net Income (Loss) (Details) - Cumberland and PRB Transaction - Discontinued Operations - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Revenues:    
Total revenues   $ 235,509
Costs and expenses:    
Cost of coal sales (exclusive of items shown separately below)   215,390
Depreciation, depletion and amortization   11,570
Accretion on asset retirement obligations   4,154
Asset impairment and restructuring   172,640
Selling, general and administrative expenses   1,623
Other income   (926)
Other non-major expense items, net   374
Loss on sale   36,113
Loss from discontinued operations before income taxes $ 1,660 $ (205,429)
v3.22.0.1
Discontinued Operations - Major Components of Asset and Liabilities (Details) - Cumberland and PRB Transaction - Discontinued Operations - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Assets:    
Trade accounts receivable, net of allowance for doubtful accounts $ 0 $ 7,504
Prepaid expenses and other current assets 462 3,431
Other non-current assets (1) 8,526 9,473
Liabilities:    
Trade accounts payable, accrued expenses and other current liabilities 5,838 12,306
Workers’ compensation and black lung obligations, non-current 23,683 27,799
Other non-current liabilities $ 0 $ 1,291
v3.22.0.1
Discontinued Operations - Major Components of Cash Flows (Details) - Cumberland and PRB Transaction - Discontinued Operations
$ in Thousands
 12 Months Ended
Dec. 31, 2020
USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]  
Depreciation, depletion and amortization $ 11,570
Capital expenditures 34,411
Other significant operating non-cash items related to discontinued operations:  
Accretion on asset retirement obligations 4,154
Asset impairment and restructuring $ 172,640
v3.22.0.1
Revenue - Disaggregation of Revenue by Segment (Details)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
USD ($)
segment
Dec. 31, 2020
USD ($)
segment
Revenue from Contract with Customer [Abstract]    
Number of reportable segments | segment 1 2
Disaggregation of Revenue [Line Items]    
Revenues $ 2,252,597 $ 1,413,124
Met Coal    
Disaggregation of Revenue [Line Items]    
Revenues 2,071,307 1,232,775
Thermal Coal    
Disaggregation of Revenue [Line Items]    
Revenues 181,290 180,349
Export coal revenues    
Disaggregation of Revenue [Line Items]    
Revenues 1,706,026 898,025
Export coal revenues | Met Coal    
Disaggregation of Revenue [Line Items]    
Revenues 1,675,147 870,121
Export coal revenues | Thermal Coal    
Disaggregation of Revenue [Line Items]    
Revenues 30,879 27,904
Domestic coal revenues    
Disaggregation of Revenue [Line Items]    
Revenues 546,571 515,099
Domestic coal revenues | Met Coal    
Disaggregation of Revenue [Line Items]    
Revenues 396,160 362,654
Domestic coal revenues | Thermal Coal    
Disaggregation of Revenue [Line Items]    
Revenues $ 150,411 $ 152,445
v3.22.0.1
Revenue - Performance Obligations (Details)
$ in Thousands
Dec. 31, 2021
USD ($)
Disaggregation of Revenue [Line Items]  
Estimated coal revenues $ 79,967
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01  
Disaggregation of Revenue [Line Items]  
Estimated coal revenues $ 65,768
Estimated coal revenues, period 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01  
Disaggregation of Revenue [Line Items]  
Estimated coal revenues $ 14,199
Estimated coal revenues, period 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01  
Disaggregation of Revenue [Line Items]  
Estimated coal revenues $ 0
Estimated coal revenues, period 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01  
Disaggregation of Revenue [Line Items]  
Estimated coal revenues $ 0
Estimated coal revenues, period 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01  
Disaggregation of Revenue [Line Items]  
Estimated coal revenues $ 0
Estimated coal revenues, period 1 year
v3.22.0.1
Accumulated Other Comprehensive Loss - Changes to Accumulated Other Comprehensive Loss (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Beginning balance $ 200,102 $ 696,122
Ending balance 546,909 200,102
Employee benefit costs    
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Beginning balance (111,985) (58,616)
Other comprehensive income before reclassifications 47,461 (60,647)
Amounts reclassified from accumulated other comprehensive loss 6,021 7,278
Ending balance $ (58,503) $ (111,985)
v3.22.0.1
Accumulated Other Comprehensive Loss - Summary of Amounts Reclassified (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Employee benefit costs:    
Income (loss) from continuing operations before income taxes $ 290,538 $ (243,634)
Income tax (expense) benefit (3,609) 2,164
Net income (loss) 288,790 (446,899)
Reclassification out of Accumulated Other Comprehensive Income | Amortization of actuarial loss    
Employee benefit costs:    
Miscellaneous income 5,653 3,929
Reclassification out of Accumulated Other Comprehensive Income | Settlement    
Employee benefit costs:    
Miscellaneous income 368 3,349
Reclassification out of Accumulated Other Comprehensive Income | Employee benefit costs    
Employee benefit costs:    
Income (loss) from continuing operations before income taxes 6,021 7,278
Income tax (expense) benefit 0 0
Net income (loss) $ 6,021 $ 7,278
v3.22.0.1
Net Income (Loss) per Share - Narrative (Details) - shares
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Earnings Per Share [Abstract]    
Antidilutive securities excluded from computation of earnings per share (in shares) 717,992 1,317,351
Weighted-average antidilutive securities excluded from computation of earnings per share (in shares)   142,250
v3.22.0.1
Net Income (Loss) per Share - Schedule of Net Income (Loss) Per Common Share (Details) - USD ($)
$ / shares in Units, $ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Net income (loss)    
Income (loss) from continuing operations $ 286,929 $ (241,470)
Income (loss) from discontinued operations 1,861 (205,429)
Net income (loss) $ 288,790 $ (446,899)
Basic    
Weighted average common shares outstanding - basic (in shares) 18,441,175 18,298,362
Basic income (loss) per common share:    
Income (loss) from continuing operations (in dollars per share) $ 15.56 $ (13.20)
Income (loss) from discontinued operations (in dollars per share) 0.10 (11.22)
Net income (loss) (in dollars per share) $ 15.66 $ (24.42)
Diluted    
Weighted average common shares outstanding - basic (in shares) 18,441,175 18,298,362
Weighted average common shares outstanding - diluted (in shares) 18,871,682 18,298,362
Diluted income (loss) per common share:    
Income (loss) from continuing operations (in dollars per share) $ 15.20 $ (13.20)
Income (loss) from discontinuing operations (in dollars per share) 0.10 (11.22)
Net income (loss) (in dollars per share) $ 15.30 $ (24.42)
Warrants    
Diluted    
Diluted effect of share-based payment awards (in shares) 35,574 0
Stock options    
Diluted    
Diluted effect of share-based payment awards (in shares) 1,753 0
Other stock-based instruments    
Diluted    
Diluted effect of share-based payment awards (in shares) 393,180 0
v3.22.0.1
Inventories, net (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2021
Inventory [Line Items]    
Total inventories, net $ 108,051 $ 129,382
Allowance for obsolete materials and supplies inventory 807  
Coal revenues    
Inventory [Line Items]    
Raw coal 15,084 20,347
Saleable coal 69,262 81,240
Materials, supplies and other, net    
Inventory [Line Items]    
Materials, supplies and other, net $ 23,705 $ 27,795
v3.22.0.1
Asset Impairment and Restructuring - Narrative (Details)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2020
USD ($)
Sep. 30, 2020
USD ($)
Jun. 30, 2020
USD ($)
Mar. 31, 2020
USD ($)
Dec. 31, 2021
USD ($)
Dec. 31, 2020
USD ($)
assetGroup
Impaired Long-Lived Assets Held and Used [Line Items]            
Total long-lived asset impairment $ 29,636 $ 3,516 $ 161,738 $ 33,709   $ 228,599
Strategic Actions with Respect to Two Thermal Coal Mining Complexes            
Impaired Long-Lived Assets Held and Used [Line Items]            
Restructuring expense           $ 27,919
Discontinued Operations            
Impaired Long-Lived Assets Held and Used [Line Items]            
Number of assets impaired | assetGroup           1
Discontinued Operations | Strategic Actions with Respect to Two Thermal Coal Mining Complexes            
Impaired Long-Lived Assets Held and Used [Line Items]            
Restructuring expense           $ 24,995
All Other            
Impaired Long-Lived Assets Held and Used [Line Items]            
Total long-lived asset impairment         $ 60  
Number of assets impaired | assetGroup           3
All Other | Strategic Actions with Respect to Two Thermal Coal Mining Complexes            
Impaired Long-Lived Assets Held and Used [Line Items]            
Restructuring expense         $ (621)  
Operating segments | Met            
Impaired Long-Lived Assets Held and Used [Line Items]            
Number of assets impaired | assetGroup           5
v3.22.0.1
Asset Impairment and Restructuring - Long-Lived Asset Impairments (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2020
Sep. 30, 2020
Jun. 30, 2020
Mar. 31, 2020
Dec. 31, 2021
Dec. 31, 2020
Impaired Long-Lived Assets Held and Used [Line Items]            
Long-lived asset impairment, continuing operations $ 29,636 $ 219 $ 17,390 $ 33,709   $ 80,954
Long-lived asset impairment, discontinued operations 0 3,297 144,348 0   147,645
Total long-lived asset impairment 29,636 3,516 161,738 33,709   228,599
Mineral rights, net            
Impaired Long-Lived Assets Held and Used [Line Items]            
Long-lived asset impairment, continuing operations 17,513 0 2,241 21,825   41,579
Long-lived asset impairment, discontinued operations 0 0 16,364 0   16,364
Total long-lived asset impairment 17,513 0 18,605 21,825   57,943
Property, plant, and equipment, net            
Impaired Long-Lived Assets Held and Used [Line Items]            
Long-lived asset impairment, continuing operations 5,450 219 6,496 6,066 $ 60 18,231
Long-lived asset impairment, discontinued operations 0 3,297 127,984 0   131,281
Total long-lived asset impairment 5,450 3,516 134,480 6,066   149,512
Acquired mine permits, net            
Impaired Long-Lived Assets Held and Used [Line Items]            
Long-lived asset impairment, continuing operations 6,673 0 8,653 5,818   21,144
Total long-lived asset impairment 6,673 0 8,653 5,818   21,144
Operating segments | Met            
Impaired Long-Lived Assets Held and Used [Line Items]            
Long-lived asset impairment, continuing operations 13,366 0 0 32,951   46,317
All Other            
Impaired Long-Lived Assets Held and Used [Line Items]            
Long-lived asset impairment, continuing operations $ 16,270 $ 219 $ 17,390 $ 758   $ 34,637
Total long-lived asset impairment         $ 60  
v3.22.0.1
Asset Impairment and Restructuring - Restructuring Expense (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Restructuring Cost and Reserve [Line Items]    
Allowance for obsolete materials and supplies inventory   $ 807
Strategic Actions with Respect to Two Thermal Coal Mining Complexes    
Restructuring Cost and Reserve [Line Items]    
Severance and employee-related benefits   26,037
Other costs   1,882
Restructuring expense   27,919
Deferred longwall move expenses   668
Allowance for advanced mining royalties   407
Allowance for obsolete materials and supplies inventory   807
Strategic Actions with Respect to Two Thermal Coal Mining Complexes | All Other    
Restructuring Cost and Reserve [Line Items]    
Restructuring expense $ (621)  
Strategic Actions with Respect to Two Thermal Coal Mining Complexes | Continuing Operations    
Restructuring Cost and Reserve [Line Items]    
Severance and employee-related benefits   2,117
Other costs   807
Restructuring expense   2,924
Strategic Actions with Respect to Two Thermal Coal Mining Complexes | Continuing Operations | All Other    
Restructuring Cost and Reserve [Line Items]    
Restructuring expense   2,924
Strategic Actions with Respect to Two Thermal Coal Mining Complexes | Discontinued Operations    
Restructuring Cost and Reserve [Line Items]    
Severance and employee-related benefits   23,920
Other costs   1,075
Restructuring expense   $ 24,995
v3.22.0.1
Prepaid Expenses and Other Current Assets (Details) - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]    
Prepaid freight $ 19,671 $ 8,515
Notes and other receivables 4,161 13,245
Short-term restricted cash 11,977 9,311
Prepaid insurance 8,525 6,510
Refundable income taxes 0 64,565
Prepaid bond premium 1,649 2,576
Other prepaid expenses 1,707 1,530
Total prepaid expenses and other current assets $ 47,690 $ 106,252
v3.22.0.1
Property, Plant, and Equipment, Net - Schedule of Property, Plant, and Equipment, Net (Details) - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Property, Plant and Equipment [Line Items]    
Total property, equipment and mine development costs $ 806,074 $ 746,043
Less accumulated depreciation, depletion and amortization (443,856) (382,423)
Total property, plant, and equipment, net 362,218 363,620
Plant and mining equipment    
Property, Plant and Equipment [Line Items]    
Total property, equipment and mine development costs 642,874 603,463
Mine development    
Property, Plant and Equipment [Line Items]    
Total property, equipment and mine development costs 115,357 96,008
Land    
Property, Plant and Equipment [Line Items]    
Total property, equipment and mine development costs 26,389 26,606
Office equipment, software and other    
Property, Plant and Equipment [Line Items]    
Total property, equipment and mine development costs 1,462 1,379
Construction in progress    
Property, Plant and Equipment [Line Items]    
Total property, equipment and mine development costs $ 19,992 $ 18,587
v3.22.0.1
Property, Plant, and Equipment, Net - Narrative (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2020
Sep. 30, 2020
Jun. 30, 2020
Mar. 31, 2020
Dec. 31, 2021
Dec. 31, 2020
Property, Plant and Equipment [Line Items]            
Depreciation, depletion and amortization associated with property, plant and equipment         $ 86,506 $ 153,631
Revisions to asset retirement obligations         12,744 43,765
Impairment of long-lived assets $ 29,636 $ 219 $ 17,390 $ 33,709   80,954
Equipment purchase commitments            
Property, Plant and Equipment [Line Items]            
Purchase commitment, 2022         18,497  
Property, plant, and equipment, net            
Property, Plant and Equipment [Line Items]            
Impairment of long-lived assets 5,450 $ 219 $ 6,496 $ 6,066 60 18,231
Depreciation expense            
Property, Plant and Equipment [Line Items]            
Revisions to asset retirement obligations         (307) (3,689)
Plant and mining equipment            
Property, Plant and Equipment [Line Items]            
Financing leases included in plant and mining equipment 7,907       8,611 7,907
Financing leases, accumulated depreciation $ 3,645       $ 5,624 $ 3,645
v3.22.0.1
Other Non-Current Assets (Details) - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]    
Advanced mining royalties $ 10,788 $ 13,132
Long-term deposits 1,371 28,200
Long-term restricted investments 28,443 23,768
Equity method investments 20,460 18,383
Workers’ compensation receivables 45,335 48,320
Other 24,660 17,579
Total other non-current assets $ 131,057 $ 149,382
v3.22.0.1
Leases - Right-of-use Assets and Lease Liabilities (Details) - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Assets    
Financing lease assets $ 2,987 $ 4,262
Operating lease right-of-use assets 5,003 5,671
Total lease assets $ 7,990 $ 9,933
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] Property, plant, and equipment, net of accumulated depreciation and amortization of $443,856 and $382,423 as of December 31, 2021 and 2020, respectively Property, plant, and equipment, net of accumulated depreciation and amortization of $443,856 and $382,423 as of December 31, 2021 and 2020, respectively
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] Other non-current assets Other non-current assets
Liabilities    
Financing lease liabilities - current $ 1,878 $ 2,014
Operating lease liabilities - current 547 595
Financing lease liabilities - long-term 791 1,996
Operating lease liabilities - long-term 4,456 5,076
Total lease liabilities $ 7,672 $ 9,681
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] Current portion of long-term debt Current portion of long-term debt
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List] Accrued expenses and other current liabilities Accrued expenses and other current liabilities
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List] Long-term debt, net of current portion Long-term debt, net of current portion
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List] Other non-current liabilities Other non-current liabilities
v3.22.0.1
Leases - Lease Costs and Other Information (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Financing lease cost:    
Amortization of leased assets $ 2,061 $ 3,238
Interest on lease liabilities 245 358
Operating lease cost 1,383 2,105
Short-term lease cost 786 1,518
Total lease cost 4,475 7,219
Sublease income 0 0
Variable lease income 0 0
Other information    
Cash paid for amounts included in the measurement of lease liabilities 4,478 7,157
Operating cash flows from financing leases 245 358
Operating cash flows from operating leases 2,169 3,623
Financing cash flows from financing leases 2,064 3,176
Right-of-use assets obtained in exchange for new financing lease liabilities 703 221
Right-of-use assets obtained in exchange for new operating lease liabilities $ 275 $ (12)
Lease Term and Discount Rate    
Weighted-average remaining lease term in years - financing leases 1 year 9 months 1 year 11 months 8 days
Weighted-average remaining lease term in years - operating leases 7 years 10 months 17 days 8 years 5 months 12 days
Weighted-average discount rate - financing leases 9.60% 6.10%
Weighted-average discount rate - operating leases 11.30% 11.50%
v3.22.0.1
Leases - Maturities of Lease Liabilities (Details)
$ in Thousands
Dec. 31, 2021
USD ($)
Financing Leases  
2022 $ 2,072
2023 522
2024 259
2025 150
2026 3
Thereafter 0
Total future minimum lease payments 3,006
Imputed interest (337)
Present value of future minimum lease payments 2,669
Operating Leases  
2022 1,100
2023 1,066
2024 955
2025 897
2026 884
Thereafter 2,775
Total future minimum lease payments 7,677
Imputed interest (2,674)
Present value of future minimum lease payments $ 5,003
v3.22.0.1
Accrued Expenses and Other Current Liabilities (Details) - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Payables and Accruals [Abstract]    
Wages and benefits $ 52,310 $ 40,330
Workers’ compensation 10,582 10,355
Black lung 7,235 6,784
Taxes other than income taxes 30,734 21,540
Current portion of asset retirement obligations 32,159 24,990
Accrued interest and fees 14,489 15,902
Deferred revenue 0 13,197
Freight accrual 15,085 2,610
Other 12,013 4,698
Accrued expenses and other current liabilities $ 174,607 $ 140,406
v3.22.0.1
Long-Term Debt - Schedule of Long-Term Debt (Details) - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Debt Instrument [Line Items]    
Debt discount and issuance costs $ (6,195) $ (17,046)
Total long-term debt 448,551 582,527
Less current portion (2,989) (28,830)
Long-term debt, net of current portion 445,562 553,697
Term Loan | Term Loan Credit Facility - due June 2024    
Debt Instrument [Line Items]    
Total long-term debt, gross 449,435 553,373
Line of Credit | ABL Facility - due December 2024    
Debt Instrument [Line Items]    
Total long-term debt, gross 0 3,350
Note Payable | LCC Note Payable    
Debt Instrument [Line Items]    
Total long-term debt, gross 0 27,500
Less current portion   (17,500)
Note Payable | LCC Water Treatment Obligation    
Debt Instrument [Line Items]    
Total long-term debt, gross 0 6,875
Less current portion   (1,875)
Other    
Debt Instrument [Line Items]    
Total long-term debt, gross $ 5,311 $ 8,475
v3.22.0.1
Long-Term Debt - Term Loan Credit Facility (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2021
Sep. 30, 2021
Jun. 14, 2019
Sep. 30, 2021
Dec. 31, 2021
Dec. 31, 2020
Debt Instrument [Line Items]            
Outstanding borrowings $ 454,746       $ 454,746  
Repurchase of debt, net of discount         18,415 $ 0
Term Loan Credit Facility - due June 2024 | Term Loan            
Debt Instrument [Line Items]            
Repurchased amount   $ 18,724   $ 18,724    
Repurchase of debt, net of discount       $ 18,415    
Payment of borrowings 50,000 $ 31,000        
Term Loan | Term Loan Credit Facility - due June 2024            
Debt Instrument [Line Items]            
Aggregate amount of debt     $ 561,800      
Principal payments due in March, June, September and December     $ 1,405      
Outstanding borrowings $ 443,241       $ 443,241 540,643
Current maturities           $ 5,618
Term Loan | Term Loan Credit Facility - due June 2024 | Base Rate | Debt Instrument, Interest Rate, Period Two            
Debt Instrument [Line Items]            
Variable interest rate (as a percent)     7.00%      
Term Loan | Term Loan Credit Facility - due June 2024 | Base Rate | Debt Instrument, Interest Rate, Period One            
Debt Instrument [Line Items]            
Variable interest rate (as a percent)     6.00%      
Term Loan | Term Loan Credit Facility - due June 2024 | Eurocurrency            
Debt Instrument [Line Items]            
Variable interest rate (as a percent)         8.00%  
Variable floor rate (as a percent)     2.00%      
Interest rate at period end (as a percent) 10.00%       10.00%  
Term Loan | Term Loan Credit Facility - due June 2024 | Eurocurrency | Debt Instrument, Interest Rate, Period Two            
Debt Instrument [Line Items]            
Variable interest rate (as a percent)     8.00%      
Term Loan | Term Loan Credit Facility - due June 2024 | Eurocurrency | Debt Instrument, Interest Rate, Period One            
Debt Instrument [Line Items]            
Variable interest rate (as a percent)     7.00%      
v3.22.0.1
Long-Term Debt - Second Amended and Restated Asset-Based Revolving Credit Agreement (Details) - USD ($)
Dec. 06, 2021
Dec. 31, 2021
Debt Instrument [Line Items]    
Outstanding borrowings   $ 454,746,000
Revolving Credit Facility | New ABL Facility    
Debt Instrument [Line Items]    
Amount of credit facility $ 155,000,000  
Letter of Credit | New ABL Facility    
Debt Instrument [Line Items]    
Amount of credit facility 150,000,000  
Amount of credit facility on committed basis 125,000,000  
Amount of credit facility on uncommitted basis $ 25,000,000  
Commitment fee (as a percent) 0.50%  
Fronting fee (as a percent) 0.25%  
Line of Credit | New ABL Facility    
Debt Instrument [Line Items]    
Letter of credit fee (as a percent) 5.25%  
Letters of credit outstanding   121,037,000
Line of Credit | Revolving Credit Facility | New ABL Facility    
Debt Instrument [Line Items]    
Outstanding borrowings   0
Letters of credit outstanding   $ 121,037,000
Line of Credit | Revolving Credit Facility | New ABL Facility | Base Rate    
Debt Instrument [Line Items]    
Variable interest rate (as a percent) 3.50%  
Line of Credit | Revolving Credit Facility | New ABL Facility | SOFR    
Debt Instrument [Line Items]    
Variable interest rate (as a percent) 4.50%  
v3.22.0.1
Long-Term Debt - Amended and Restated Asset-Based Revolving Credit Agreement (Details) - USD ($)
$ in Thousands
 1 Months Ended 3 Months Ended 12 Months Ended
Nov. 09, 2018
Jan. 31, 2021
Mar. 31, 2021
Dec. 31, 2020
Dec. 31, 2021
Dec. 06, 2021
Mar. 20, 2020
Debt Instrument [Line Items]              
Outstanding borrowings         $ 454,746    
Revolving Credit Facility | ABL Facility              
Debt Instrument [Line Items]              
Amount of credit facility $ 225,000            
Repayments of remaining borrowings     $ 3,350        
Letter of Credit | ABL Facility              
Debt Instrument [Line Items]              
Amount of credit facility $ 200,000            
Fronting fee (as a percent) 0.25%            
Letter of Credit | ABL Facility | Minimum              
Debt Instrument [Line Items]              
Commitment fee (as a percent) 0.25%            
Letter of Credit | ABL Facility | Maximum              
Debt Instrument [Line Items]              
Commitment fee (as a percent) 0.375%            
Line of Credit | ABL Facility              
Debt Instrument [Line Items]              
Letters of credit outstanding       $ 123,108      
Line of Credit | Revolving Credit Facility | ABL Facility              
Debt Instrument [Line Items]              
Outstanding borrowings       $ 3,350   $ 0 $ 57,500
Collateral posted   $ 25,000          
Line of Credit | Revolving Credit Facility | ABL Facility | Base Rate | Minimum              
Debt Instrument [Line Items]              
Variable interest rate (as a percent) 1.00%            
Line of Credit | Revolving Credit Facility | ABL Facility | Base Rate | Maximum              
Debt Instrument [Line Items]              
Variable interest rate (as a percent) 1.50%            
Line of Credit | Revolving Credit Facility | ABL Facility | Eurocurrency              
Debt Instrument [Line Items]              
Variable interest rate (as a percent)       2.50%      
Interest rate at period end (as a percent)       2.73%      
Line of Credit | Revolving Credit Facility | ABL Facility | Eurocurrency | Minimum              
Debt Instrument [Line Items]              
Variable interest rate (as a percent) 2.00%            
Line of Credit | Revolving Credit Facility | ABL Facility | Eurocurrency | Maximum              
Debt Instrument [Line Items]              
Variable interest rate (as a percent) 2.50%            
v3.22.0.1
Long-Term Debt - LCC Note Payable and Water Treatment Stipulation (Details) - USD ($)
 1 Months Ended
Jul. 26, 2021
Nov. 09, 2018
Oct. 31, 2021
Dec. 31, 2021
Dec. 31, 2020
Debt Instrument [Line Items]          
Outstanding borrowings       $ 454,746,000  
Current portion of long-term debt       $ 2,989,000 $ 28,830,000
LCC Note Payable | Notes Payable, Other Payables          
Debt Instrument [Line Items]          
Payment of final principal $ 7,700,000   $ 2,300,000    
LCC Water Treatment Obligation | Notes Payable, Other Payables          
Debt Instrument [Line Items]          
Payment of final principal     $ 5,000,000    
Notes Payable, Other Payables | LCC Note Payable          
Debt Instrument [Line Items]          
Aggregate amount of debt   $ 62,500,000      
Imputed interest rate       12.45%  
Annual debt repayments   17,500,000      
Final debt repayment   10,000,000      
Surety collateral returned $ 13,982,000        
Outstanding borrowings       $ 0 24,423,000
Current portion of long-term debt         17,500,000
Notes Payable, Other Payables | LCC Water Treatment Obligation          
Debt Instrument [Line Items]          
Aggregate amount of debt   12,500,000      
Imputed interest rate       13.12%  
Annual debt repayments   $ 625,000      
Outstanding borrowings       $ 0 5,636,000
Current portion of long-term debt         $ 1,875,000
v3.22.0.1
Long-Term Debt - Schedule of Long-Term Debt Maturities (Details)
$ in Thousands
Dec. 31, 2021
USD ($)
Debt Disclosure [Abstract]  
2022 $ 2,989
2023 1,367
2024 450,245
2025 142
2026 3
Total long-term debt $ 454,746
v3.22.0.1
Acquisition-Related Obligations - Components (Details) - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Fair Value, Option, Quantitative Disclosures [Line Items]    
Discount $ (233) $ (1,491)
Total acquisition-related obligations 41,405 39,867
Less current portion (22,405) (19,099)
Acquisition-related obligations, net of current portion 19,000 20,768
Contingent Revenue Obligation    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Total acquisition-related obligations 35,005 28,967
Total acquisition-related obligations 35,005 28,967
Less current portion (16,005) (11,393)
Environmental Settlement Obligations    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Total acquisition-related obligations 6,633 10,391
Discount (233) (1,154)
Total acquisition-related obligations 6,400 9,237
Less current portion (6,400) (6,044)
UMWA Funds Settlement Liability    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Total acquisition-related obligations $ 0 $ 2,000
v3.22.0.1
Acquisition-Related Obligations - Narrative (Details) - USD ($)
 3 Months Ended
Jun. 30, 2021
Jun. 30, 2020
Dec. 31, 2021
Dec. 31, 2020
Nov. 09, 2018
Business Acquisition, Contingent Consideration [Line Items]          
Liabilities held for sale     $ 41,405,000 $ 39,867,000  
Acquisition related obligations, current     22,405,000 19,099,000  
Discount     233,000 1,491,000  
Contingent Revenue Obligation, Threshold One          
Business Acquisition, Contingent Consideration [Line Items]          
Percentage of revenue         1.50%
Revenue threshold         $ 500,000,000
Contingent Revenue Obligation, Threshold Two          
Business Acquisition, Contingent Consideration [Line Items]          
Percentage of revenue         1.00%
Revenue threshold         $ 500,000,000
Contingent Revenue Obligation          
Business Acquisition, Contingent Consideration [Line Items]          
Liabilities held for sale     35,005,000 28,967,000  
Acquisition related obligations, current     16,005,000 11,393,000  
Payment of contingent revenue obligation $ 11,396,000 $ 15,084,000      
Unclaimed unsecured claims   $ 374,000      
Environmental Settlement Obligations          
Business Acquisition, Contingent Consideration [Line Items]          
Liabilities held for sale     6,400,000 9,237,000  
Acquisition related obligations, current     6,400,000 6,044,000  
Discount     $ 233,000 $ 1,154,000  
v3.22.0.1
Asset Retirement Obligation (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Asset Retirement Obligation Disclosure [Abstract]    
Total asset retirement obligations, beginning balance $ 165,064 $ 203,137
Accretion for the period 26,520 26,504
Sites added during the period 2,125 621
Revisions in estimated cash flows (12,744) (43,765)
Expenditures for the period (16,793) (21,433)
Total assets retirement obligation, ending balance 164,172 165,064
Less current portion (32,159) (24,990)
Long-term portion $ 132,013 $ 140,074
v3.22.0.1
Fair Value of Financial Instruments and Fair Value Measurements - Total Long-Term Debt (Details) - Fair Value, Measurements, Nonrecurring - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Quoted Prices in Active Markets (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt $ 0 $ 0
Significant Other Observable Inputs (Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt 447,561 379,614
Significant Unobservable Inputs (Level 3)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt 0 27,666
Term Loan | Term Loan Credit Facility - due June 2024 | Quoted Prices in Active Markets (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt 0 0
Term Loan | Term Loan Credit Facility - due June 2024 | Significant Other Observable Inputs (Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt 447,561 379,614
Term Loan | Term Loan Credit Facility - due June 2024 | Significant Unobservable Inputs (Level 3)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt 0 0
Line of Credit | ABL Facility | Quoted Prices in Active Markets (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt   0
Line of Credit | ABL Facility | Significant Other Observable Inputs (Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt   0
Line of Credit | ABL Facility | Significant Unobservable Inputs (Level 3)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt   3,057
Note Payable | LCC Note Payable | Quoted Prices in Active Markets (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt   0
Note Payable | LCC Note Payable | Significant Other Observable Inputs (Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt   0
Note Payable | LCC Note Payable | Significant Unobservable Inputs (Level 3)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt   20,328
Note Payable | LCC Water Treatment Obligation | Quoted Prices in Active Markets (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt   0
Note Payable | LCC Water Treatment Obligation | Significant Other Observable Inputs (Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt   0
Note Payable | LCC Water Treatment Obligation | Significant Unobservable Inputs (Level 3)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt   4,281
Carrying Amount    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt 443,241 574,052
Carrying Amount | Term Loan | Term Loan Credit Facility - due June 2024    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt 443,241 540,643
Carrying Amount | Line of Credit | ABL Facility    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt   3,350
Carrying Amount | Note Payable | LCC Note Payable    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt   24,423
Carrying Amount | Note Payable | LCC Water Treatment Obligation    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt   5,636
Total Fair Value    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt 447,561 407,280
Total Fair Value | Term Loan | Term Loan Credit Facility - due June 2024    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt $ 447,561 379,614
Total Fair Value | Line of Credit | ABL Facility    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt   3,057
Total Fair Value | Note Payable | LCC Note Payable    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt   20,328
Total Fair Value | Note Payable | LCC Water Treatment Obligation    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total long-term debt   $ 4,281
v3.22.0.1
Fair Value of Financial Instruments and Fair Value Measurements - Acquisition-related Obligations at Fair Value (Details) - Fair Value, Measurements, Nonrecurring - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Carrying Amount    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total acquisition-related obligations $ 6,400 $ 10,899
Carrying Amount | UMWA Funds Settlement Liability    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total acquisition-related obligations   1,662
Carrying Amount | Environmental Settlement Obligations    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total acquisition-related obligations 6,400 9,237
Total Fair Value    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total acquisition-related obligations 6,270 9,186
Total Fair Value | Quoted Prices in Active Markets (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total acquisition-related obligations 0 0
Total Fair Value | Significant Other Observable Inputs (Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total acquisition-related obligations 0 0
Total Fair Value | Significant Unobservable Inputs (Level 3)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total acquisition-related obligations 6,270 9,186
Total Fair Value | UMWA Funds Settlement Liability    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total acquisition-related obligations   1,426
Total Fair Value | UMWA Funds Settlement Liability | Quoted Prices in Active Markets (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total acquisition-related obligations   0
Total Fair Value | UMWA Funds Settlement Liability | Significant Other Observable Inputs (Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total acquisition-related obligations   0
Total Fair Value | UMWA Funds Settlement Liability | Significant Unobservable Inputs (Level 3)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total acquisition-related obligations   1,426
Total Fair Value | Environmental Settlement Obligations    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total acquisition-related obligations 6,270 7,760
Total Fair Value | Environmental Settlement Obligations | Quoted Prices in Active Markets (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total acquisition-related obligations 0 0
Total Fair Value | Environmental Settlement Obligations | Significant Other Observable Inputs (Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total acquisition-related obligations 0 0
Total Fair Value | Environmental Settlement Obligations | Significant Unobservable Inputs (Level 3)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total acquisition-related obligations $ 6,270 $ 7,760
v3.22.0.1
Fair Value of Financial Instruments and Fair Value Measurements - Schedule of Fair Value on Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]    
Contingent Revenue Obligation $ 35,005 $ 28,967
Trading securities 28,443 22,498
Quoted Prices in Active Markets (Level 1)    
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]    
Contingent Revenue Obligation 0 0
Trading securities 27,075 20,092
Significant Other Observable Inputs (Level 2)    
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]    
Contingent Revenue Obligation 0 0
Trading securities 1,368 2,406
Significant Unobservable Inputs (Level 3)    
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]    
Contingent Revenue Obligation 35,005 28,967
Trading securities $ 0 $ 0
v3.22.0.1
Fair Value of Financial Instruments and Fair Value Measurements - Level 3 of the Fair Value Hierarchy (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance $ 28,967 $ 52,427
Payments   (14,710)
Gain Recognized in Earnings   (8,750)
Transfer In (Out) of Level 3 Fair Value Hierarchy   0
Ending balance   28,967
Significant Unobservable Inputs (Level 3)    
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance 28,967  
Payments (13,487)  
Gain Recognized in Earnings 19,525  
Transfer In (Out) of Level 3 Fair Value Hierarchy 0  
Ending balance $ 35,005 $ 28,967
v3.22.0.1
Fair Value of Financial Instruments and Fair Value Measurements - Narrative (Details) - Fair Value, Measurements, Recurring - Significant Unobservable Inputs (Level 3) - Valuation Technique, Discounted Cash Flow - Measurement Input, Discount Rate
Dec. 31, 2021
Dec. 31, 2020
Notes Payable, Other Payables, Environmental Settlement Obligations, and United Mine Workers of America Funds Settlement Liability    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Long-term debt and acquisition-related obligations, measurement input 0.13 0.34
Line of Credit | ABL Facility    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Long-term debt, measurement input   0.09
v3.22.0.1
Fair Value of Financial Instruments and Fair Value Measurements - Unobservable Inputs (Details) - Black Scholes - Contingent Revenue Obligation - USD ($)
$ in Billions
Dec. 31, 2021
Dec. 31, 2020
Forecasted future revenue | Minimum    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Forecasted future revenue $ 1.5 $ 0.9
Forecasted future revenue | Maximum    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Forecasted future revenue $ 2.0 $ 1.1
Stated royalty rate | Minimum    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Acquisition-related obligation, measurement input 1.00% 1.00%
Stated royalty rate | Maximum    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Acquisition-related obligation, measurement input 1.50% 1.50%
Annualized volatility | Minimum    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Acquisition-related obligation, measurement input 18.40% 19.40%
Annualized volatility | Maximum    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Acquisition-related obligation, measurement input 39.30% 52.10%
Annualized volatility | Weighted Average    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Acquisition-related obligation, measurement input 29.90% 28.00%
v3.22.0.1
Income Taxes - Total Income Tax Expense (Benefit) Provided on Income Before Income Taxes (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Income Tax Disclosure [Abstract]    
Continuing operations $ 3,609 $ (2,164)
Discontinued operations (201) 0
Total $ 3,408 $ (2,164)
v3.22.0.1
Income Taxes - Components of Income Tax Expense (Benefit) (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Current tax expense (benefit):    
Federal $ 2,586 $ (35,187)
State 1,186 (99)
Total current 3,772 (35,286)
Deferred tax (benefit) expense:    
Federal (3) 33,348
State (160) (226)
Total deferred (163) 33,122
Total income tax expense (benefit):    
Federal 2,583 (1,839)
State 1,026 (325)
Income tax expense (benefit) $ 3,609 $ (2,164)
v3.22.0.1
Income Taxes - Effective Income Tax Reconciliation (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Income Tax Disclosure [Abstract]    
Federal statutory income tax expense (benefit) $ 61,013 $ (51,163)
Increase (reductions) in taxes due to:    
Percentage depletion allowance (11,864) (2,039)
AMT sequestration refund 0 (2,123)
State taxes, net of federal tax impact 12,998 (9,640)
State apportioned tax rate change, net of federal tax impact 8,751 (1,235)
Change in valuation allowances (78,056) 59,929
Capital loss expiration 10,552 0
Stock-based compensation 405 1,739
Other, net (190) 2,368
Income tax expense (benefit) $ 3,609 $ (2,164)
v3.22.0.1
Income Taxes - Deferred Income Taxes (Details) - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Deferred tax assets:      
Asset retirement obligations $ 36,252 $ 41,268  
Reserves and accruals not currently deductible 9,610 12,131  
Workers’ compensation benefit obligations 47,105 59,478  
Pension obligations 34,956 52,598  
Equity method investments 1,846 2,050  
Loss carryforwards, net of Section 382 limitation 187,341 255,772  
Acquisition-related obligations 9,156 10,002  
Other 7,100 10,976  
Gross deferred tax assets 333,366 444,275  
Less valuation allowance (172,883) (263,387) $ (133,020)
Deferred tax assets 160,483 180,888  
Deferred tax liabilities:      
Property, plant and mineral reserves (134,075) (141,549)  
Acquired intangibles, net (16,408) (22,037)  
Prepaid expenses (4,955) (6,211)  
Restricted cash (5,362) (11,516)  
Other 0 (55)  
Total deferred tax liabilities (160,800) (181,368)  
Net deferred tax liabilities $ (317) $ (480)  
v3.22.0.1
Income Taxes - Valuation Allowance (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Valuation Allowance, Deferred Tax Asset, Increase (Decrease) [Roll Forward]    
Valuation allowance beginning of period $ 263,387 $ 133,020
(Decrease) increase in valuation allowance recorded to income tax expense (benefit) (78,043) 117,829
(Decrease) increase in valuation allowance not affecting income tax expense (benefit) (12,461) 12,538
Valuation allowance end of period $ 172,883 $ 263,387
v3.22.0.1
Income Taxes - Narrative (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2020
Dec. 31, 2020
Dec. 31, 2021
Mar. 31, 2020
Dec. 31, 2019
Tax Credit Carryforward [Line Items]          
AMT credit refund received, other   $ 2,123      
Operating loss carryforwards     $ 1,543,000    
Operating loss carryforwards available to offset regular federal taxable income     1,008,000    
Operating loss carryforwards section 382 limitation one     1,000    
Operating loss carryforwards subject to section 382 limitation two     270,000    
Operating loss carryforwards section 382 limitation three     17,500    
Operating loss carryforwards, indefinite carryforwards     265,000    
Reasonably possible decrease in unrecognized tax benefits     20,788    
Interest and penalties related to uncertain tax positions $ 0 $ 0 0    
Tax Year 2016 | IRS          
Tax Credit Carryforward [Line Items]          
Carryback claim tax refund received     64,160    
Accrued interest refunded     5,425    
Capital Loss Carryforward          
Tax Credit Carryforward [Line Items]          
Capital loss carryforwards     $ 223,000    
Prepaid Expenses and Other Current Assets          
Tax Credit Carryforward [Line Items]          
Federal income taxes receivable         $ 33,065
Deferred tax assets related to AMT credits       $ 33,065 $ 33,065
AMT credit refund received, CARES Act $ 66,130        
v3.22.0.1
Income Taxes - Reconciliation for Uncertain Tax Position (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]    
Unrecognized tax benefits - beginning of period $ 0 $ 20,788
Reductions for tax positions of prior years 0 (20,788)
Unrecognized tax benefits - end of period $ 0 $ 0
v3.22.0.1
Employee Benefit Plans - Narrative (Details)
$ in Thousands
 1 Months Ended 3 Months Ended 12 Months Ended
Oct. 01, 2019
plan
Nov. 09, 2018
plan
Sep. 30, 2020
Jun. 30, 2021
USD ($)
Dec. 31, 2020
USD ($)
Dec. 31, 2022
Dec. 31, 2021
USD ($)
Dec. 31, 2020
USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Number of plans amended | plan 2              
Period for incremental increase of target allocation     10 months          
Contributions to defined contribution and profit sharing plans             $ 10,276 $ 3,613
Self-insured medical expense             $ 63,127 $ 52,517
Pension Plan                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Expected return on plan assets (as a percent)             5.80% 5.90%
Funded percentage             90.00%  
Target allocation percentage, incremental increases     2.00%          
Employer contributions             $ 6,571 $ 22,745
Expected contributions in next fiscal year             4,404  
Partial plan settlement             3,815 11,627
Accelerated recognition of portion of the accumulated other comprehensive loss             (412) (1,636)
Benefit obligation         $ 218,671   $ 159,930 $ 218,671
Pension Plan | Equity Securities                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Target allocation (as a percent)     60.00%       50.00%  
Pension Plan | Debt Securities                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Target allocation (as a percent)     40.00%       50.00%  
Pension Plan | Forecast                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Expected return on plan assets (as a percent)           5.80%    
Funded percentage           90.00%    
Target allocation (as a percent)           100.00%    
Black Lung                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Expected return on plan assets (as a percent)             2.00% 2.00%
Employer contributions             $ 6,040 $ 7,166
High-deductible insurance premium expense for worker's compensation and black lung claims             8,602 7,000
Workers' compensation expense for high-deductible insurance plans             3,750 1,275
Partial plan settlement         8,290   0 8,290
Accelerated recognition of portion of the accumulated other comprehensive loss         1,563   0 (1,563)
Increase in liability offset to accumulated other comprehensive loss       $ 7,400     0 (163)
Benefit obligation         124,786   114,478 124,786
Life Insurance Benefits                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Benefit obligation         12,635   11,610 12,635
Life Insurance Benefits | Current Liabilities                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Benefit obligation         $ 628   $ 602 $ 628
Alpha Companies                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Number of plans assumed | plan   3            
Alpha Companies | Pension Plan | Qualified Plan | Frozen Defined Benefit Pension Plan, Pre 2004 Balance                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Guaranteed rates of interest on accumulated balances             6.00%  
Alpha Companies | Pension Plan | Qualified Plan | Frozen Defined Benefit Pension Plan, Post 2004 Balance                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Guaranteed rates of interest on accumulated balances             4.00%  
v3.22.0.1
Employee Benefit Plans - Changes in Accumulated Benefits Obligations, Fair Value of Plan Assets and Funded Status of Plan (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Jun. 30, 2021
Dec. 31, 2020
Dec. 31, 2021
Dec. 31, 2020
Pension Plan        
Change in benefit obligation:        
Accumulated benefit obligation at beginning of period     $ 723,448 $ 674,439
Interest cost     13,566 18,730
Actuarial (gain) loss     (34,922) 72,822
Benefits paid     (30,222) (30,916)
Settlement     (3,815) (11,627)
Accumulated benefit obligation at end of period   $ 723,448 668,055 723,448
Change in fair value of plan assets:        
Beginning balance     504,777 470,353
Actual return on plan assets     30,814 54,222
Employer contributions     6,571 22,745
Benefits paid     (30,222) (30,916)
Settlement     (3,815) (11,627)
Ending balance   504,777 508,125 504,777
Funded status   (218,671) (159,930) (218,671)
Summary of accrued benefit cost at end of period:        
Accrued benefit cost at end of period   (218,671) (159,930) (218,671)
Black Lung        
Change in benefit obligation:        
Accumulated benefit obligation at beginning of period     127,506 122,788
Service cost     2,972 2,361
Interest cost     2,463 3,240
Actuarial (gain) loss     (9,759) 14,736
Benefits paid     (6,040) (7,166)
Curtailment gain $ 7,400   0 (163)
Settlement   (8,290) 0 (8,290)
Accumulated benefit obligation at end of period   127,506 117,142 127,506
Change in fair value of plan assets:        
Beginning balance     2,720 2,660
Actual return on plan assets     (56) 60
Employer contributions     6,040 7,166
Benefits paid     (6,040) (7,166)
Ending balance   2,720 2,664 2,720
Funded status   (124,786) (114,478) (124,786)
Summary of accrued benefit cost at end of period:        
Accrued benefit cost at end of period   (124,786) (114,478) (124,786)
Black Lung | Continuing Operations        
Summary of accrued benefit cost at end of period:        
Accrued benefit cost at end of period   (122,961) (111,854) (122,961)
Black Lung | Discontinued Operations        
Summary of accrued benefit cost at end of period:        
Accrued benefit cost at end of period   $ (1,825) $ (2,624) $ (1,825)
v3.22.0.1
Employee Benefit Plans - Gross Amounts Recognized in Accumulated Other Comprehensive (Income) Loss (Details) - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Pension Plan    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Net actuarial gain (loss) $ 47,950 $ 88,583
Black Lung    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Net actuarial gain (loss) $ 11,940 $ 24,042
v3.22.0.1
Employee Benefit Plans - Schedule of Components of Net Periodic Benefit Cost (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Pension Plan    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Interest cost $ 13,566 $ 18,730
Expected return on plan assets (28,732) (27,064)
Amortization of net actuarial loss (gain) 3,217 2,012
Settlement 412 1,636
Net periodic benefit cost (credit) (11,537) (4,686)
Black Lung    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Service cost 2,972 2,361
Interest cost 2,463 3,240
Expected return on plan assets (54) (54)
Amortization of net actuarial loss (gain) 2,453 1,942
Settlement 0 1,563
Net periodic benefit cost (credit) 7,834 9,052
Continuing Operations | Black Lung    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Net periodic benefit cost (credit) 7,418 7,670
Discontinued Operations | Black Lung    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Net periodic benefit cost (credit) $ 416 $ 1,382
v3.22.0.1
Employee Benefit Plans - Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive (Income) Loss (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2020
Dec. 31, 2021
Dec. 31, 2020
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Actuarial (gain) loss   $ (47,461) $ 60,647
Amortization of net actuarial gain (loss)   (6,021) (7,278)
Pension Plan      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Actuarial (gain) loss   (37,004) 45,663
Amortization of net actuarial gain (loss)   (3,217) (2,012)
Settlement   (412) (1,636)
Total recognized in other comprehensive income (loss)   (40,633) 42,015
Black Lung      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Actuarial (gain) loss   (9,649) 14,567
Amortization of net actuarial gain (loss)   (2,453) (1,942)
Settlement $ 1,563 0 (1,563)
Total recognized in other comprehensive income (loss)   $ (12,102) $ 11,062
v3.22.0.1
Employee Benefit Plans - Schedule of Plans with Benefit Obligations in Excess of Plan Assets (Details) - Pension Plan - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]    
Projected benefit obligation $ 668,055 $ 723,448
Accumulated benefit obligation 668,055 723,448
Fair value of plan assets $ 508,125 $ 504,777
v3.22.0.1
Employee Benefit Plans - Assumptions Used (Details)
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Pension Plan    
Weighted-Average Assumptions to Determine Benefit Obligations    
Discount rate 2.92% 2.62%
Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost    
Discount rate for benefit obligation 2.62% 3.35%
Discount rate for interest cost 1.96% 2.92%
Expected return on plan assets 5.80% 5.90%
Black Lung    
Weighted-Average Assumptions to Determine Benefit Obligations    
Discount rate 2.96% 2.75%
Federal black lung income benefit trend rate 2.00% 2.00%
Federal black lung medical benefit trend rate 5.00% 5.00%
Black lung benefit expense inflation rate 0.00% 2.00%
Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost    
Discount rate for benefit obligation 2.75% 3.47%
Discount rate for service cost 3.15% 3.56%
Discount rate for interest cost 1.96% 2.61%
Federal black lung income benefit trend rate 2.00% 2.50%
Federal black lung medical benefit trend rate 5.00% 5.00%
Black lung benefit expense inflation rate 0.00% 2.00%
Expected return on plan assets 2.00% 2.00%
v3.22.0.1
Employee Benefit Plans - Allocation of Plan Assets (Details) - Pension Plan
Dec. 31, 2022
Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]    
Percentage of Plan Assets   100.00%
Funded status level (less than)   90.00%
Forecast    
Defined Benefit Plan Disclosure [Line Items]    
Target Allocation Percentage 100.00%  
Funded status level (less than) 90.00%  
Equity securities    
Defined Benefit Plan Disclosure [Line Items]    
Percentage of Plan Assets   56.00%
Equity securities | Forecast    
Defined Benefit Plan Disclosure [Line Items]    
Target Allocation Percentage 60.00%  
Fixed income funds    
Defined Benefit Plan Disclosure [Line Items]    
Percentage of Plan Assets   41.00%
Fixed income funds | Forecast    
Defined Benefit Plan Disclosure [Line Items]    
Target Allocation Percentage 40.00%  
Other    
Defined Benefit Plan Disclosure [Line Items]    
Percentage of Plan Assets   3.00%
Other | Forecast    
Defined Benefit Plan Disclosure [Line Items]    
Target Allocation Percentage 0.00%  
v3.22.0.1
Employee Benefit Plans - Estimated Cash Payments (Details)
$ in Thousands
Dec. 31, 2021
USD ($)
Pension Plan  
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]  
2022 $ 30,949
2023 30,944
2024 31,161
2025 31,497
2026 31,657
2027-2031 158,207
Estimated future cash payments 314,415
Black Lung  
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]  
2022 7,295
2023 7,208
2024 7,254
2025 7,329
2026 7,497
2027-2031 19,889
Estimated future cash payments $ 56,472
v3.22.0.1
Employee Benefit Plans - Fair Value of Plan Assets (Details) - Pension Plan - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets $ 508,125 $ 504,777 $ 470,353
Significant Unobservable Inputs (Level 3)      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 11,652 11,454 $ 11,155
Defined Benefit Plan, Assets After Receivables For Investments Sold      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 506,946 503,370  
Receivable      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 876 888  
Defined Benefit Plan, Assets Before Receivables For Investments Sold | Total      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 506,070 502,482  
Defined Benefit Plan, Assets Before Receivables For Investments Sold | Quoted Prices in Active Markets (Level 1)      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0 0  
Defined Benefit Plan, Assets Before Receivables For Investments Sold | Significant Observable Inputs (Level 2)      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 494,418 491,028  
Defined Benefit Plan, Assets Before Receivables For Investments Sold | Significant Unobservable Inputs (Level 3)      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 11,652 11,454  
Equity securities | Total      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 284,568 236,405  
Equity securities | Quoted Prices in Active Markets (Level 1)      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0 0  
Equity securities | Significant Observable Inputs (Level 2)      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 284,568 236,405  
Equity securities | Significant Unobservable Inputs (Level 3)      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0 0  
Fixed income funds | Total      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 208,466 253,218  
Fixed income funds | Quoted Prices in Active Markets (Level 1)      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0 0  
Fixed income funds | Significant Observable Inputs (Level 2)      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 208,466 253,218  
Fixed income funds | Significant Unobservable Inputs (Level 3)      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0 0  
Commingled short-term fund | Total      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 1,384 1,405  
Commingled short-term fund | Quoted Prices in Active Markets (Level 1)      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0 0  
Commingled short-term fund | Significant Observable Inputs (Level 2)      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 1,384 1,405  
Commingled short-term fund | Significant Unobservable Inputs (Level 3)      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0 0  
Guaranteed insurance contract | Total      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 11,652 11,454  
Guaranteed insurance contract | Quoted Prices in Active Markets (Level 1)      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0 0  
Guaranteed insurance contract | Significant Observable Inputs (Level 2)      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0 0  
Guaranteed insurance contract | Significant Unobservable Inputs (Level 3)      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 11,652 11,454  
Private equity funds      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets $ 1,179 $ 1,407  
Defined Benefit Plan, Plan Assets, Fair Value by Hierarchy and NAV [Extensible List] Fair Value Measured at Net Asset Value Per Share [Member] Fair Value Measured at Net Asset Value Per Share [Member]  
v3.22.0.1
Employee Benefit Plans - Schedule of Changes in Level 3 Assets (Details) - Pension Plan - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]    
Beginning balance $ 504,777 $ 470,353
Ending balance 508,125 504,777
Significant Unobservable Inputs (Level 3)    
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]    
Beginning balance 11,454 11,155
Relating to assets still held at the reporting date 528 659
Purchases, sales and settlements (330) (360)
Ending balance $ 11,652 $ 11,454
v3.22.0.1
Employee Benefit Plans - Workers' Compensation (Details) - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Retirement Benefits [Abstract]    
Current liabilities $ 10,582 $ 10,355
Current liabilities - discontinued operations 2,730 4,847
Long-term liabilities 103,574 113,904
Long-term liabilities - discontinued operations 21,119 26,000
Total liabilities 138,005 155,106
Less expected insurance receivable (47,644) (50,688)
Less long-term expected insurance receivable - discontinued operations (6,020) (6,970)
Workers’ compensation obligations, net of expected insurance receivables $ 84,341 $ 97,448
v3.22.0.1
Employee Benefit Plans - Amounts Recognized in Balance Sheet (Details) - Black Lung - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Accrued benefit cost at end of period $ 114,478 $ 124,786
Current liabilities    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Accrued benefit cost at end of period 7,235 6,784
Current liabilities - discontinued operations    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Accrued benefit cost at end of period 60 26
Long-term liabilities    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Accrued benefit cost at end of period 104,619 116,177
Long-term liabilities - discontinued operations    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Accrued benefit cost at end of period $ 2,564 $ 1,799
v3.22.0.1
Stock-Based Compensation Awards - Narrative (Details)
$ / shares in Units, $ in Thousands
 3 Months Ended 12 Months Ended
Nov. 09, 2018
shares
Mar. 31, 2021
shares
Dec. 31, 2021
USD ($)
award_type
$ / shares
shares
Dec. 31, 2020
USD ($)
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of award types | award_type     4  
Stock compensation expense | $     $ 7,468 $ 5,540
Time-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted     223,496  
Grant date fair value (in USD per share) | $ / shares     $ 12.03  
Number of shares forfeited     4,920  
Unrecognized compensation cost of non-vested shares | $     $ 1,167  
Unrecognized compensation cost, period for recognition     1 year 3 months 29 days  
Operational performance-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted     100,552  
Grant date fair value (in USD per share) | $ / shares     $ 12.00  
Number of shares forfeited     151,398  
Unrecognized compensation cost of non-vested shares | $     $ 386  
Unrecognized compensation cost, period for recognition     2 years 29 days  
Relative performance-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted     67,035  
Grant date fair value (in USD per share) | $ / shares     $ 16.18  
Number of shares forfeited     153,016  
Unrecognized compensation cost of non-vested shares | $     $ 803  
Unrecognized compensation cost, period for recognition     1 year 11 months 12 days  
Performance-based cash incentive awards        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Target award amount for cash-based incentive plans | $     $ 927  
Weighted average grant date fair value, percentage of target dollar value     51.73%  
Unrecognized compensation cost of non-vested shares | $     $ 2,092  
Unrecognized compensation cost, period for recognition     1 year 4 months 20 days  
Absolute performance-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted     0  
Grant date fair value (in USD per share) | $ / shares     $ 0  
Number of shares forfeited     541  
Unrecognized compensation cost of non-vested shares | $     $ 13  
Unrecognized compensation cost, period for recognition     1 month 9 days  
30-Day volume-weighted average price stock options        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Unrecognized compensation cost | $     $ 0  
CEO | Minimum | Performance-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Potential distribution of shares (as a percent)       0.00%
CEO | Maximum | Performance-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Potential distribution of shares (as a percent)       200.00%
Employee | Minimum | Performance-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Potential distribution of shares (as a percent)     0.00%  
Employee | Maximum | Performance-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Potential distribution of shares (as a percent)     200.00%  
Selling, General and Administrative Expenses        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock-based compensation expense (as a percent)     89.00% 83.00%
MIP        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares authorized for issuance     1,201,202  
Number of shares available for grant     37,805  
LTIP        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares authorized for issuance     1,500,000  
Number of shares available for grant     870,503  
LTIP | Performance-based cash incentive awards        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Weighted average grant date fair value, percentage of target dollar value     51.73%  
LTIP | CEO | Performance-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted       302,795
Vesting period       3 years
Number of shares forfeited   302,795    
LTIP | CEO | Operational performance-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted       151,398
Closing price (in USD per share) | $ / shares       $ 6.36
LTIP | CEO | Relative performance-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted       151,397
Grant date fair value (in USD per share) | $ / shares       $ 8.53
LTIP | Employee | Performance-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted     167,587  
Vesting period     3 years  
LTIP | Employee | Operational performance-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted     100,552  
Closing price (in USD per share) | $ / shares     $ 12.00  
LTIP | Employee | Relative performance-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted     67,035  
Grant date fair value (in USD per share) | $ / shares     $ 16.18  
LTIP | Employee | Performance-based cash incentive awards        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Vesting period     3 years  
Target award amount for cash-based incentive plans | $     $ 927 $ 2,755
Liability for cash-based awards | $     $ 255  
Weighted average grant date fair value, percentage of target dollar value       82.45%
LTIP | Employee | Minimum | Performance-based cash incentive awards        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Potential distribution of cash-based payments (as a percent)     0.00% 0.00%
LTIP | Employee | Maximum | Performance-based cash incentive awards        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Potential distribution of cash-based payments (as a percent)     200.00% 200.00%
ANR EIP        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares authorized for issuance     0  
Number of shares available for grant     0  
Number of share awards granted 89,766      
MIP and LTIP        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares repurchased     50,363  
Common stock reissuances, repurchases and related expenses | $     $ 785  
Share repurchase price (in USD per share) | $ / shares     $ 15.60  
MIP and LTIP | Time-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted     223,496 402,620
Grant date fair value (in USD per share) | $ / shares     $ 12.03 $ 6.17
Vesting period     3 years 3 years
MIP, LTIP, and ANR EIP        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares repurchased       43,559
Common stock reissuances, repurchases and related expenses | $       $ 209
Share repurchase price (in USD per share) | $ / shares       $ 4.79
2020 LTIP | Employee | Performance-based cash incentive awards        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Liability for cash-based awards | $     $ 2,542 $ 643
v3.22.0.1
Stock-Based Compensation Awards - Valuation Assumptions (Details)
 12 Months Ended
Dec. 31, 2021
$ / shares
Dec. 31, 2020
d
$ / shares
Dec. 31, 2019
d
Relative performance-based restricted stock units      
Share-based Payment Award      
Start price (in USD per share) $ 11.81 $ 7.59  
Stock price (in USD per share) $ 11.34 $ 6.33  
Expected volatility (as a percent) 98.54% 55.27%  
Risk-free interest rate (as a percent) 0.18% 1.37%  
Expected dividend yield (as a percent) 0.00% 0.00%  
Cash-based Payment Award      
Average closing stock price, threshold trading days | d   20 20
Performance-based cash incentive awards      
Cash-based Payment Award      
Start price (in USD per share) $ 11.81 $ 7.59  
Valuation date stock price (in USD per share) $ 11.34 $ 6.33  
Expected volatility (as a percent) 98.54% 55.27%  
Risk-free interest rate (as a percent) 0.18% 1.37%  
Expected divided yield (as a percent) 0.00% 0.00%  
Average closing stock price, threshold trading days | d   20 20
v3.22.0.1
Stock-Based Compensation Awards - Award Activity (Details) - $ / shares
 3 Months Ended 12 Months Ended
Mar. 31, 2022
Dec. 31, 2021
Time-based restricted stock units    
Number of Shares    
Beginning balance (in shares) 392,275 367,553
Granted (in shares)   223,496
Vested (in shares)   (193,854)
Forfeited or Cancelled (in shares)   (4,920)
Ending balance (in shares)   392,275
Weighted-Average Grant  Date Fair Value    
Beginning balance (in USD per share) $ 11.54 $ 13.72
Granted (in USD per share)   12.03
Vested (in USD per share)   16.05
Forfeited or Cancelled (in USD per share)   19.22
Ending balance (in USD per share)   $ 11.54
Restricted stock units and deferred settlements    
Number of Shares    
Vested (in shares)   (61,646)
Relative performance-based restricted stock units    
Number of Shares    
Beginning balance (in shares) 88,222 174,203
Granted (in shares)   67,035
Vested (in shares)   0
Forfeited or Cancelled (in shares)   (153,016)
Ending balance (in shares)   88,222
Weighted-Average Grant  Date Fair Value    
Beginning balance (in USD per share) $ 28.07 $ 16.01
Granted (in USD per share)   16.18
Vested (in USD per share)   0
Forfeited or Cancelled (in USD per share)   9.13
Ending balance (in USD per share)   $ 28.07
Relative performance-based restricted stock units | Forecast    
Number of Shares    
Forfeited or Cancelled (in shares) (46,551)  
Absolute performance-based restricted stock units    
Number of Shares    
Beginning balance (in shares) 7,073 7,614
Granted (in shares)   0
Vested (in shares)   0
Forfeited or Cancelled (in shares)   (541)
Ending balance (in shares)   7,073
Weighted-Average Grant  Date Fair Value    
Beginning balance (in USD per share) $ 50.60 $ 50.60
Granted (in USD per share)   0
Vested (in USD per share)   0
Forfeited or Cancelled (in USD per share)   50.60
Ending balance (in USD per share)   $ 50.60
Absolute performance-based restricted stock units | Forecast    
Number of Shares    
Forfeited or Cancelled (in shares) (15,532)  
Operational performance-based restricted stock units    
Number of Shares    
Beginning balance (in shares) 100,552 151,398
Granted (in shares)   100,552
Vested (in shares)   0
Forfeited or Cancelled (in shares)   (151,398)
Ending balance (in shares)   100,552
Weighted-Average Grant  Date Fair Value    
Beginning balance (in USD per share) $ 12.00 $ 6.36
Granted (in USD per share)   12.00
Vested (in USD per share)   0
Forfeited or Cancelled (in USD per share)   6.36
Ending balance (in USD per share)   $ 12.00
v3.22.0.1
Stock-Based Compensation Awards - Option Activity (Details) - 30-Day volume-weighted average price stock options - USD ($)
$ / shares in Units, $ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Number of Shares    
Beginning balance, outstanding (in shares) 23,225  
Beginning balance, exercisable (in shares) 23,225  
Granted (in shares) 0  
Exercised (in shares) 0  
Forfeited or Expired (in shares) 0  
Ending balance, outstanding (in shares) 23,225 23,225
Ending balance, exercisable (in shares) 23,225 23,225
Weighted-Average Exercise Price Per Share    
Beginning balance, outstanding (in USD per share) $ 60.20  
Beginning balance, exercisable (in USD per share) 60.20  
Granted (in USD per share) 0  
Exercised (in USD per share) 0  
Forfeited or Expired (in USD per share) 0  
Ending balance, outstanding (in USD per share) 60.20 $ 60.20
Ending balance, exercisable (in USD per share) $ 60.20 $ 60.20
Weighted-Average Remaining Contractual Term (Years)    
Outstanding 5 years 1 month 13 days 6 years 1 month 13 days
Exercisable 5 years 1 month 13 days 6 years 1 month 13 days
Aggregate Intrinsic Value    
Beginning balance, outstanding $ (1,134)  
Beginning balance, exercisable (1,134)  
Exercised 0  
Ending balance, outstanding 20 $ (1,134)
Ending balance, exercisable $ 20 $ (1,134)
v3.22.0.1
Stock-Based Compensation Awards - Performance-Based Cash Incentive Awards (Details) - Performance-based cash incentive awards
$ in Thousands
 12 Months Ended
Dec. 31, 2021
USD ($)
Target Dollar Value  
Non-vested awards outstanding at December 31, 2020 $ 2,206
Granted 927
Vested 0
Forfeited (142)
Non-vested awards outstanding at December 31, 2021 $ 2,991
Weighted-Average Fair Value as a % of Target Dollar Value  
Non-vested awards outstanding at December 31, 2020 (as a percent) 94.21%
Granted (as a percent) 51.73%
Vested (as a percent) 0.00%
Forfeited (as a percent) 78.45%
Non-vested awards outstanding at December 31, 2021 (as a percent) 162.03%
v3.22.0.1
Related Party Transactions (Details) - Privately Negotiated Transaction with a Contingent Revenue Obligation Creditor - Shareholder
$ in Thousands
 12 Months Ended
Dec. 31, 2021
USD ($)
Related Party Transaction [Line Items]  
Percentage of contingent revenue obligation 7.75%
Aggregate purchase price of outstanding rights $ 2,091
v3.22.0.1
Commitments and Contingencies - Narrative (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Feb. 10, 2022
Feb. 21, 2020
Feb. 20, 2020
Long-term Purchase Commitment [Line Items]          
Coal royalty expense $ 113,685 $ 67,992      
Black lung          
Long-term Purchase Commitment [Line Items]          
Collateral for black lung obligations       $ 65,700 $ 2,600
Black lung | Subsequent Event          
Long-term Purchase Commitment [Line Items]          
Collateral for black lung obligations     $ 10,000    
New ABL Facility | Line of Credit          
Long-term Purchase Commitment [Line Items]          
Letters of credit outstanding 121,037        
New ABL Facility | Line of Credit | Revolving Credit Facility          
Long-term Purchase Commitment [Line Items]          
Letters of credit outstanding 121,037        
Credit and Security Agreement | Line of Credit | Revolving Credit Facility          
Long-term Purchase Commitment [Line Items]          
Letters of credit outstanding 613        
Surety bond          
Long-term Purchase Commitment [Line Items]          
Outstanding surety bonds 176,119        
Obligations and commitments attributable to discontinued operations 30        
Reclamation-related obligations          
Long-term Purchase Commitment [Line Items]          
Letters of credit outstanding 15,548        
Reclamation-related obligations | Collateral Pledged          
Long-term Purchase Commitment [Line Items]          
Restricted cash, restricted investments and deposits 36,792        
Equipment purchase commitments          
Long-term Purchase Commitment [Line Items]          
Purchase commitment, 2022 18,497        
Diesel fuel purchase commitments          
Long-term Purchase Commitment [Line Items]          
Estimated obligation in 2022 25,490        
Coal purchase agreements          
Long-term Purchase Commitment [Line Items]          
Purchase commitment, 2022 37,335        
Royalty obligations | Coal          
Long-term Purchase Commitment [Line Items]          
Minimum obligation, 2022 14,665        
Minimum obligation, 2023 14,418        
Minimum obligation, 2024 13,620        
Minimum obligation, 2025 12,525        
Minimum obligation, 2026 12,396        
Minimum obligation, after 2026 56,771        
Coal transportation agreements          
Long-term Purchase Commitment [Line Items]          
Minimum obligation, 2022 2,527        
Minimum obligation, 2023 105,750        
Minimum obligation, 2024 $ 87,825        
v3.22.0.1
Commitments and Contingencies - Restricted Cash (Details) - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Long-term Purchase Commitment [Line Items]    
Total restricted cash $ 101,403 $ 105,344
Less current portion (11,977) (9,311)
Restricted cash, net of current portion 89,426 96,033
Workers’ compensation and black lung obligations    
Long-term Purchase Commitment [Line Items]    
Total restricted cash 70,637 69,725
Reclamation-related obligations    
Long-term Purchase Commitment [Line Items]    
Total restricted cash 10,449 8,445
Financial payments and other performance obligations    
Long-term Purchase Commitment [Line Items]    
Total restricted cash 8,340 17,863
Contingent Revenue Obligation escrow    
Long-term Purchase Commitment [Line Items]    
Total restricted cash $ 11,977 $ 9,311
v3.22.0.1
Commitments and Contingencies - Restricted Investments (Details) - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Long-term Purchase Commitment [Line Items]    
Total restricted investments $ 28,443 $ 23,768
Restricted trading securities 28,443 22,498
Restricted held-to-maturity securities 0 1,270
Workers’ compensation obligations    
Long-term Purchase Commitment [Line Items]    
Total restricted investments 210 51
Reclamation-related obligations    
Long-term Purchase Commitment [Line Items]    
Total restricted investments 26,225 22,233
Financial payments and other performance obligations    
Long-term Purchase Commitment [Line Items]    
Total restricted investments $ 2,008 $ 1,484
v3.22.0.1
Commitments and Contingencies - Total Deposits (Details) - USD ($)
$ in Thousands
Dec. 31, 2021
Dec. 31, 2020
Long-term Purchase Commitment [Line Items]    
Total deposits $ 1,394 $ 28,247
Reclamation-related obligations    
Long-term Purchase Commitment [Line Items]    
Total deposits 118 25,633
Financial payments and other performance obligations    
Long-term Purchase Commitment [Line Items]    
Total deposits 403 1,596
Other operating agreements    
Long-term Purchase Commitment [Line Items]    
Total deposits $ 873 $ 1,018
v3.22.0.1
Concentration of Credit Risk and Major Customer (Details)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
USD ($)
customer
Dec. 31, 2020
USD ($)
customer
Concentration Risk [Line Items]    
Revenues | $ $ 2,258,586 $ 1,416,187
Revenues | Customer Concentration Risk    
Concentration Risk [Line Items]    
Number of customers 2 2
Revenues | Customer Concentration Risk | Top Customer    
Concentration Risk [Line Items]    
Concentration risk (as a percent) 13.00% 16.00%
Revenues | Customer Concentration Risk | Top 10 Customers    
Concentration Risk [Line Items]    
Concentration risk (as a percent) 64.00% 63.00%
Revenues | Geographic Concentration Risk | Domestic Coal Revenue    
Concentration Risk [Line Items]    
Concentration risk (as a percent) 24.00% 36.00%
Revenues | Geographic Concentration Risk | Export Coal Revenue    
Concentration Risk [Line Items]    
Concentration risk (as a percent) 76.00% 64.00%
Accounts Receivable | Customer Concentration Risk    
Concentration Risk [Line Items]    
Number of customers 3 3
Coal Sales Volume | Product Concentration Risk | Met coal    
Concentration Risk [Line Items]    
Concentration risk (as a percent) 83.00% 80.00%
Coal Sales Volume | Product Concentration Risk | Thermal Coal    
Concentration Risk [Line Items]    
Concentration risk (as a percent) 17.00% 20.00%
v3.22.0.1
Segment Information - Narrative (Details)
 12 Months Ended
Dec. 31, 2021
segment
plant
mine
Dec. 31, 2020
segment
Segment Reporting Information [Line Items]    
Number of reportable segments | segment 1 2
West Virgina | All Other    
Segment Reporting Information [Line Items]    
Number of active mines | mine 1  
Number of preparation plants | plant 1  
Met | Virgina    
Segment Reporting Information [Line Items]    
Number of active mines | mine 5  
Number of preparation plants | plant 2  
Met | West Virgina    
Segment Reporting Information [Line Items]    
Number of active mines | mine 14  
Number of preparation plants | plant 5  
v3.22.0.1
Segment Information - Schedule of Operating Results and Capital Expenditures (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Segment Reporting Information [Line Items]    
Revenues $ 2,258,586 $ 1,416,187
Depreciation, depletion and amortization 110,047 139,885
Amortization of acquired intangibles, net 13,244 9,214
Adjusted EBITDA 532,823 83,401
Capital expenditures 83,300 119,579
Operating segments | Met    
Segment Reporting Information [Line Items]    
Revenues 2,176,080 1,264,496
Depreciation, depletion and amortization 99,963 124,060
Amortization of acquired intangibles, net 13,671 12,889
Adjusted EBITDA 567,270 120,281
Capital expenditures 79,185 111,745
All Other    
Segment Reporting Information [Line Items]    
Revenues 82,506 151,691
Depreciation, depletion and amortization 10,084 15,825
Amortization of acquired intangibles, net (427) (3,675)
Adjusted EBITDA (34,447) (36,880)
Capital expenditures $ 4,115 $ 7,834
v3.22.0.1
Segment Information - Reconciliation of Net Income (Loss) to Adjusted EBITDA (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Segment Reporting, Other Significant Reconciling Item [Line Items]    
Net income (loss) from continuing operations $ 286,929 $ (241,470)
Interest expense 69,654 74,528
Interest income (334) (7,027)
Income tax expense 3,609 (2,164)
Depreciation, depletion and amortization 110,047 139,885
Non-cash stock compensation expense 5,315 4,896
Mark-to-market adjustment for acquisition-related obligations 19,525 (8,750)
Gain on settlement of acquisition-related obligations (1,125)  
Accretion on asset retirement obligations 26,520 26,504
Asset impairment and restructuring (561) 83,878
Loss on partial settlement of benefit obligations   2,966
Amortization of acquired intangibles, net 13,244 9,214
Adjusted EBITDA 532,823 83,401
Senior Management Changes    
Segment Reporting, Other Significant Reconciling Item [Line Items]    
Management restructuring costs   941
Operating segments | Met    
Segment Reporting, Other Significant Reconciling Item [Line Items]    
Net income (loss) from continuing operations 439,859 (77,519)
Interest expense 184 (2,014)
Interest income (6) (63)
Income tax expense 0 0
Depreciation, depletion and amortization 99,963 124,060
Non-cash stock compensation expense 28 289
Mark-to-market adjustment for acquisition-related obligations 0 0
Gain on settlement of acquisition-related obligations 0  
Accretion on asset retirement obligations 13,571 14,214
Asset impairment and restructuring 0 46,317
Loss on partial settlement of benefit obligations   1,607
Amortization of acquired intangibles, net 13,671 12,889
Adjusted EBITDA 567,270 120,281
Operating segments | Met | Senior Management Changes    
Segment Reporting, Other Significant Reconciling Item [Line Items]    
Management restructuring costs   501
All Other    
Segment Reporting, Other Significant Reconciling Item [Line Items]    
Net income (loss) from continuing operations (152,930) (163,951)
Interest expense 69,470 76,542
Interest income (328) (6,964)
Income tax expense 3,609 (2,164)
Depreciation, depletion and amortization 10,084 15,825
Non-cash stock compensation expense 5,287 4,607
Mark-to-market adjustment for acquisition-related obligations 19,525 (8,750)
Gain on settlement of acquisition-related obligations (1,125)  
Accretion on asset retirement obligations 12,949 12,290
Asset impairment and restructuring (561) 37,561
Loss on partial settlement of benefit obligations   1,359
Amortization of acquired intangibles, net (427) (3,675)
Adjusted EBITDA $ (34,447) (36,880)
All Other | Senior Management Changes    
Segment Reporting, Other Significant Reconciling Item [Line Items]    
Management restructuring costs   $ 440
v3.22.0.1
Subsequent Events (Details)
Mar. 04, 2022
USD ($)
Subsequent Event  
Subsequent Event [Line Items]  
Share repurchase program, authorized amount $ 150,000,000
v3.22.0.1
Label Element Value
Accounting Standards Update [Extensible Enumeration] us-gaap_AccountingStandardsUpdateExtensibleList Accounting Standards Update 2016-13 [Member]