ALPHA METALLURGICAL RESOURCES, INC., 10-K filed on 2/27/2026
Annual Report
v3.25.4
Cover - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2025
Feb. 20, 2026
Jun. 30, 2025
Cover [Abstract]      
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2025    
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 Yes    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Large Accelerated Filer    
Entity Small Business false    
Entity Emerging Growth Company false    
ICFR Auditor Attestation Flag true    
Document Financial Statement Error Correction false    
Entity Shell Company false    
Entity Public Float     $ 761.0
Entity Common Stock, Shares Outstanding   12,792,685  
Documents Incorporated by Reference
Part III incorporates certain information by reference from the registrant’s definitive proxy statement for the 2026 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, 2025.
   
Entity Central Index Key 0001704715    
Document Fiscal Year Focus 2025    
Document Fiscal Period Focus FY    
Amendment Flag false    
v3.25.4
Audit Information
12 Months Ended
Dec. 31, 2025
Audit Information [Abstract]  
Auditor Name RSM US LLP
Auditor Location Charlotte, North Carolina
Auditor Firm ID 49
v3.25.4
CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Revenues:      
Coal revenues $ 2,122,605 $ 2,946,579 $ 3,456,630
Other revenues 6,876 10,706 14,787
Total revenues 2,129,481 2,957,285 3,471,417
Costs and expenses:      
Cost of coal sales (exclusive of items shown separately below) 1,924,691 2,451,601 2,356,138
Depreciation, depletion and amortization 174,524 167,331 136,869
Accretion on asset retirement obligations 22,126 25,050 25,500
Amortization of acquired intangibles 5,427 6,700 8,523
Selling, general and administrative expenses (exclusive of depreciation, depletion and amortization shown separately above) 60,158 74,000 82,390
Other operating loss (income) 3,921 4,749 (1,088)
Total costs and expenses 2,190,847 2,729,431 2,608,332
(Loss) income from operations (61,366) 227,854 863,085
Other (expense) income:      
Interest expense (3,019) (3,811) (6,923)
Interest income 15,466 18,208 11,933
Loss on extinguishment of debt 0 0 (2,753)
Equity loss in affiliates (24,867) (20,302) (18,263)
Miscellaneous expense, net (13,673) (11,199) (1,620)
Total other expense, net (26,093) (17,104) (17,626)
(Loss) income before income taxes (87,459) 210,750 845,459
Income tax benefit (expense) 25,772 (23,171) (123,503)
Net (loss) income $ (61,687) $ 187,579 $ 721,956
Basic (loss) income per common share (in dollars per share) $ (4.75) $ 14.41 $ 51.18
Diluted (loss) income per common share (in dollars per share) $ (4.75) $ 14.28 $ 49.30
Weighted average shares - basic (in shares) 12,996,148 13,013,469 14,106,466
Weighted average shares - diluted (in shares) 12,996,148 13,134,806 14,642,856
v3.25.4
CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Statement of Other Comprehensive Income [Abstract]      
Net (loss) income $ (61,687) $ 187,579 $ 721,956
Employee benefit plans:      
Current period actuarial loss (18,880) (16,659) (34,205)
Income tax benefit 4,114 3,696 7,588
Current period actuarial (loss) gain, net of income tax (14,766) (12,963) (26,617)
Less: reclassification adjustments for amounts reclassified to earnings due to amortization of net actuarial loss (gain) and settlements 5,645 4,457 (2,324)
Income tax (expense) benefit (1,230) (989) 516
Reclassification adjustments for amounts reclassified to earnings due to amortization of net actuarial loss (gain) and settlements, net of income tax 4,415 3,468 (1,808)
Total other comprehensive loss, net of tax (10,351) (9,495) (28,425)
Total comprehensive (loss) income $ (72,038) $ 178,084 $ 693,531
v3.25.4
CONSOLIDATED BALANCE SHEETS - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Current assets:    
Cash and cash equivalents $ 365,974 $ 481,578
Short-term investments 49,582 0
Trade accounts receivable, net of allowance for credit losses of $2,519 and $2,396 as of December 31, 2025 and 2024, respectively 278,620 362,141
Inventories, net 193,000 169,269
Prepaid expenses and other current assets 31,132 23,681
Total current assets 918,308 1,036,669
Property, plant, and equipment, net of accumulated depreciation and amortization of $774,101 and $667,260 as of December 31, 2025 and 2024, respectively 621,866 634,871
Owned and leased mineral rights, net of accumulated depletion and amortization of $150,616 and $124,965 as of December 31, 2025 and 2024, respectively 416,944 443,467
Other acquired intangibles, net of accumulated amortization of $43,072 and $41,444 as of December 31, 2025 and 2024, respectively 34,452 39,879
Long-term restricted cash 126,911 122,583
Long-term restricted investments 34,356 43,131
Deferred income taxes 8,087 6,516
Other non-current assets 119,702 111,592
Total assets 2,280,626 2,438,708
Current liabilities:    
Current portion of long-term debt 3,575 2,916
Trade accounts payable 66,169 96,633
Accrued expenses and other current liabilities 135,778 151,560
Total current liabilities 205,522 251,109
Long-term debt 9,841 2,868
Workers’ compensation and black lung obligations 190,965 182,961
Pension obligations 87,317 100,597
Asset retirement obligations 204,745 189,805
Deferred income taxes 15,433 40,486
Other non-current liabilities 21,308 21,385
Total liabilities 735,131 789,211
Commitments and Contingencies (Note 20)
Stockholders’ Equity    
Preferred stock - par value $0.01, 5,000,000 shares authorized, none issued 0 0
Common stock - par value $0.01, 50,000,000 shares authorized, 22,437,379 issued and 12,805,909 outstanding at December 31, 2025 and 22,383,325 issued and 13,016,390 outstanding at December 31, 2024 224 224
Additional paid-in capital 852,030 839,804
Accumulated other comprehensive loss (60,433) (50,082)
Treasury stock, at cost: 9,631,470 shares at December 31, 2025 and 9,366,935 shares at December 31, 2024 (1,341,027) (1,296,916)
Retained earnings 2,094,701 2,156,467
Total stockholders’ equity 1,545,495 1,649,497
Total liabilities and stockholders’ equity $ 2,280,626 $ 2,438,708
v3.25.4
CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Statement of Financial Position [Abstract]    
Accounts receivable, allowance for credit loss, current $ 2,519 $ 2,396
Property, plant and equipment, accumulated depreciation and amortization 774,101 667,260
Owned and leased mineral rights, accumulated depletion and amortization 150,616 124,965
Other acquired intangibles, accumulated amortization $ 43,072 $ 41,444
Preferred stock, par value (in dollars per share) $ 0.01 $ 0.01
Preferred stock, shares authorized (in shares) 5,000,000 5,000,000
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 50,000,000
Common stock, shares issued (in shares) 22,437,379 22,383,325
Common stock, shares outstanding (in shares) 12,805,909 13,016,390
Treasury stock, shares at cost (in shares) 9,631,470 9,366,935
v3.25.4
CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Operating activities:      
Net (loss) income $ (61,687) $ 187,579 $ 721,956
Adjustments to reconcile net (loss) income to net cash provided by operating activities:      
Depreciation, depletion and amortization 174,524 167,331 136,869
Amortization of acquired intangibles 5,427 6,700 8,523
Loss on extinguishment of debt 0 0 2,753
Loss (gain) on disposal of assets, net 1,044 (169) (6,817)
Accretion on asset retirement obligations 22,126 25,050 25,500
Employee benefit plans, net 23,397 14,551 8,376
Deferred tax (benefit) expense (23,740) 5,563 39,722
Stock-based compensation 13,598 12,318 19,017
Equity loss in affiliates 24,867 20,302 18,263
Other, net (1,449) 1,905 1,584
Changes in operating assets and liabilities      
Trade accounts receivable, net 83,399 145,379 (102,477)
Inventories, net (21,495) 64,203 (27,900)
Prepaid expenses and other current assets (3,128) 14,658 7,596
Deposits 183 408 80,729
Other non-current assets 356 1,199 3,837
Trade accounts payable (29,141) (19,339) 15,666
Accrued expenses and other current liabilities (10,825) (5,972) (9,087)
Acquisition-related obligations 0 0 (28,254)
Workers’ compensation and black lung obligations (19,959) (18,660) (19,969)
Pension obligations (16,966) (12,320) (25,011)
Asset retirement obligations (14,721) (27,903) (19,189)
Other non-current liabilities (884) (2,864) (528)
Net cash provided by operating activities 144,926 579,919 851,159
Investing activities:      
Capital expenditures (127,153) (198,848) (245,373)
Capital contributions to equity affiliates (38,146) (32,504) (30,812)
Proceeds from disposal of assets 265 1,029 8,173
Cash paid for business acquired 0 0 (11,919)
Purchases of investment securities (106,157) (48,730) (207,065)
Sales and maturities of investment securities 67,165 48,036 320,961
Other, net 51 31 35
Net cash used in investing activities (203,975) (230,986) (166,000)
Financing activities:      
Principal repayments of long-term debt (1,965) (2,243) (2,314)
Dividend and dividend equivalents paid (415) (3,077) (113,013)
Common stock repurchases and related expenses (45,155) (122,299) (540,071)
Other, net (4,692) (1,278) (1,030)
Net cash used in financing activities (52,227) (128,897) (656,428)
Net (decrease) increase in cash and cash equivalents and restricted cash (111,276) 220,036 28,731
Cash and cash equivalents and restricted cash at beginning of period 604,161 384,125 355,394
Cash and cash equivalents and restricted cash at end of period 492,885 604,161 384,125
Supplemental cash flow information:      
Cash paid for interest 1,868 2,662 5,207
Cash paid for income taxes (net of refunds received) 2,118 8,379 79,191
Supplemental disclosure of noncash investing and financing activities:      
Financing leases and capital financing - equipment 12,057 1 3,195
Accrued capital expenditures 14,272 15,523 25,004
Accrued common stock repurchases and stock repurchase excise tax 327 0 8,118
Accrued dividend payable $ 88 $ 424 $ 2,863
v3.25.4
CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Reconciliation of Cash and Cash Equivalents and Restricted Cash        
Cash and cash equivalents $ 365,974 $ 481,578 $ 268,207  
Long-term restricted cash 126,911 122,583 115,918  
Total cash and cash equivalents and restricted cash shown in the Consolidated Statements of Cash Flows $ 492,885 $ 604,161 $ 384,125 $ 355,394
v3.25.4
CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($)
$ in Thousands
Total
Common Stock
Additional Paid-in Capital
Accumulated Other Comprehensive Loss
Treasury Stock at Cost
Retained Earnings
Beginning balance at Dec. 31, 2022 $ 1,429,755 $ 217 $ 815,442 $ (12,162) $ (649,061) $ 1,275,319
Increase (Decrease) in Stockholders' Equity [Roll Forward]            
Net (loss) income 721,956         721,956
Other comprehensive income (loss), net (28,425)     (28,425)    
Stock-based compensation, issuance of common stock for share vesting, and common stock reissuances 19,017 2 12,127   6,888  
Exercise of stock options 225   225      
Common stock repurchases and related expenses (547,542)       (547,542)  
Warrants exercises 6,690 2 6,688      
Cash dividend and dividend equivalents declared (27,748)         (27,748)
Ending balance at Dec. 31, 2023 1,573,928 221 834,482 (40,587) (1,189,715) 1,969,527
Increase (Decrease) in Stockholders' Equity [Roll Forward]            
Net (loss) income 187,579         187,579
Other comprehensive income (loss), net (9,495)     (9,495)    
Stock-based compensation, issuance of common stock for share vesting, and common stock reissuances 12,318 3 5,322   6,993  
Common stock repurchases and related expenses (114,194)       (114,194)  
Dividend equivalents (639)         (639)
Ending balance at Dec. 31, 2024 1,649,497 224 839,804 (50,082) (1,296,916) 2,156,467
Increase (Decrease) in Stockholders' Equity [Roll Forward]            
Net (loss) income (61,687)         (61,687)
Other comprehensive income (loss), net (10,351)     (10,351)    
Stock-based compensation, issuance of common stock for share vesting, and common stock reissuances 13,598 0 12,226   1,372  
Common stock repurchases and related expenses (45,483)       (45,483)  
Dividend equivalents (79)         (79)
Ending balance at Dec. 31, 2025 $ 1,545,495 $ 224 $ 852,030 $ (60,433) $ (1,341,027) $ 2,094,701
v3.25.4
CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical)
12 Months Ended
Dec. 31, 2023
$ / shares
Statement of Stockholders' Equity [Abstract]  
Dividend per share (in dollars per share) $ 1.940
v3.25.4
Business and Basis of Presentation
12 Months Ended
Dec. 31, 2025
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”) 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, previously named Contura Energy, Inc., began operations on July 26, 2016 and 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. 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. Effective February 1, 2021, the Company changed its corporate name to Alpha Metallurgical Resources, Inc. to more accurately reflect its strategic focus on the production of metallurgical coal.

Basis of Presentation

Together, the consolidated statements of operations, comprehensive (loss) income, balance sheets, cash flows and stockholders’ equity for the Company are referred to as the “Consolidated Financial Statements.” The Consolidated Financial Statements are also referenced across periods as “Consolidated Statements of Operations,” “Consolidated Statements of Comprehensive (Loss) Income,” “Consolidated Balance Sheets,” “Consolidated Statements of Cash Flows,” and “Consolidated Statements of Stockholders’ Equity.”

The Consolidated Financial Statements include all wholly owned subsidiaries’ results of operations for the years ended December 31, 2025, 2024, and 2023. 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”).
v3.25.4
Summary of Significant Accounting Policies
12 Months Ended
Dec. 31, 2025
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 payable; income taxes refundable and receivable; reserves for contingencies and litigation; and fair value of financial instruments. 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 and cash equivalents 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 20 for further information.
Investments

Short-term investments, with maturities of twelve months or less, consist of U.S government securities. Restricted investments consist of U.S. government 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.

All investments are classified as trading securities as of December 31, 2025 and 2024. Trading securities are recorded initially at cost and are adjusted to fair value at each reporting period with unrealized gains and losses recorded in current period earnings or loss. Refer to Notes 15 and 20 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 20 for further information.

Trade Accounts Receivable and Allowance for Credit Losses

Trade accounts receivable are recorded at their invoiced amounts and do not bear interest. The Company markets its coal primarily to international and domestic 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 (“LCs”), 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 21 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 6 for further information.

Advanced Mining Royalties

Lease rights to coal reserves are often acquired in exchange for royalty payments. Advanced mining royalties are advanced payments made to lessors under terms of mineral lease agreements that are recoupable against future production royalties. These advanced payments are deferred and charged to operations as the coal reserves are mined. The Company regularly reviews recoverability of advanced mining royalties and establishes or adjusts the allowance for advanced mining royalties as necessary using the specific identification method. Advanced royalty balances are generally charged off against the allowance when they are no longer recoupable. Advanced mining royalties are included within Other non-current assets on the Company’s Consolidated Balance Sheets. Refer to Note 9 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 operating loss (income) in the Company’s Consolidated Statements of Operations. Refer to Note 8 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, 2025 and 2024 were $416,944 and $443,467, respectively, and are reported in assets in the Company’s Consolidated Balance Sheets. These amounts include $37,005 and $41,552 of asset retirement obligation assets, net of accumulated amortization, associated with active mining operations for the years ended December 31, 2025 and 2024, respectively.

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 Consolidated Statements of Operations and was $22,258, $28,075, and $23,944 for the years ended December 31, 2025, 2024, and 2023 respectively.

Depletion expense for the years ended December 31, 2025, 2024, and 2023 includes a credit of ($6,137), an expense of $961, and a credit of ($34), respectively, related to revisions to asset retirement obligations. Refer to Note 14 for further disclosures related to asset retirement obligations.

Leases

In accordance with Accounting Standards Codification (“ASC”) 842 Lease Accounting (“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 11 for further information.

Acquired Intangibles

The Company has recognized assets for acquired mine permits which were valued based on the replacement cost and lost profits method as of the Merger date. The balances of such assets are included within Other acquired intangibles, net of accumulated amortization, on the Company’s Consolidated Balance Sheets. The acquired mine permits are amortized over the estimated life of the associated mine. Amortization expense is included in Amortization of acquired intangibles in the Consolidated Statements of Operations. Future net amortization expense related to acquired intangibles is expected to be $4,913, $4,837, $4,837, $4,799, $1,342, and $13,724 for 2026, 2027, 2028, 2029, 2030, and after 2030, respectively.

Goodwill

Goodwill represents the excess of the purchase price over the fair value of the net identifiable tangible and intangible assets of acquired companies. Goodwill is not amortized; instead, it is tested for impairment annually as of October 31 of each year or more frequently if indicators of impairment exist. Goodwill is included in the Consolidated Balance Sheets as Other Non-Current Assets.
The Company assesses goodwill for impairment on a qualitative basis. If the Company determines that more likely than not the fair value of a reporting unit containing goodwill exceeds its carrying amount, no further impairment testing is required. If the qualitative assessment indicates that an impairment potentially exists, then the Company quantitatively tests goodwill for impairment by comparing the fair value of the reporting unit to its carrying amount. If the fair value of the reporting unit is lower than its carrying amount, its goodwill is written down by the lesser of the amount by which the reporting units carrying amount exceeded its fair value or its carrying amount of goodwill.

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.

As of June 30, 2025, due to recent declines in metallurgical coal spot pricing, the Marfork, Power Mountain, Elk Run and Kepler mining complexes were tested for impairment. Estimated future undiscounted cash flows were projected to exceed each complex’s respective carrying value and no impairment charges were required.

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. On at least an annual basis, the Company reviews its estimated future cash flows for its asset retirement obligations. Refer to Note 14 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 16 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 3 for further information.

Workers’ Compensation and Pneumoconiosis (Black Lung) Benefits 

Workers’ Compensation

As of December 31, 2025, 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, 2025 and 2024, the workers’ compensation liability was net of a discount of $20,968 and $21,587, respectively, related to fair value adjustments associated with acquisition accounting. Refer to Note 17 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, 2025, 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 17 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 17 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 17 for further information.

Net (Loss) Income per Share

 Basic net (loss) income per share is computed by dividing net (loss) income by the weighted-average number of outstanding common shares for the period. Diluted 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 earnings per share is computed by increasing the weighted-average number of outstanding common shares computed in basic earnings per share to include the additional common shares that would be outstanding after issuance and adjusting net (loss) income 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 5 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 18 for further information.

Warrants

On July 26, 2016 (the “Initial Issue Date”), the Company issued warrants, which were classified as equity instruments, and were exercisable for cash or on a cashless basis at any time from the Initial Issue Date until July 26, 2023, and no fractional shares were issued upon warrant exercises. The exercise price and the warrant share number were adjusted in respect of certain dilutive events with respect to common stock. At 5:00 pm Eastern time on July 26, 2023 the Company’s Series A Warrants expired pursuant to their terms. Refer to Note 7 for additional information.

Equity Method Investments

Investments and membership interests in joint ventures are accounted for under the equity method of accounting if the Company has the ability to exercise significant influence, but not control, over the entity. Under the equity method of accounting, the Company’s proportionate share of the entity’s comprehensive income or loss each reporting period is reflected in Equity loss in affiliates in the Consolidated Statements of Operations. Equity method investments are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the investment may not be recoverable. The carrying values of the Company’s equity method investments are included within Other non-current assets on the Company’s Consolidated Balance Sheets. Refer to Notes 9 and 10 for additional information.

Recently Adopted Accounting Guidance

Income Tax Disclosures: In December 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (“ASU 2023-09”). This update requires public business entities to disclose in their income tax rate reconciliation table additional categories of information about federal, state, and foreign income taxes and to provide additional details about the reconciling items in categories meeting a quantitative threshold. The guidance will also require entities to disclose income taxes paid, net of refunds, disaggregated by federal, state, and foreign taxes for annual periods and to disaggregate the information by jurisdiction based
on a quantitative threshold. The additional disclosures are required to be provided on a prospective basis with the option to provide retrospectively. The amendments are effective for fiscal years beginning after December 15, 2024. The Company adopted ASU 2023-09 retrospectively during the fourth quarter of 2025 and prior period disclosures have been recast to conform to the current year presentation. Refer to Note 16 for the additional required income tax disclosures upon adoption of this ASU.

Recent Accounting Guidance Issued Not Yet Effective

Expense Disaggregation Disclosures: In November 2024, the FASB issued ASU 2024-03, Income Statement – Reporting Comprehensive Income – Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses (“ASU 2024-03”). This update requires public entities to disaggregate income statement expense line items and to disclose in tabular format within the notes to the financial statements certain categories of costs (e.g. purchases of inventory, employee compensation, deprecation, intangible asset amortization, depletion etc.) to the extent line items contain such costs. In addition, entities will be required to define and disclose selling expenses. The additional disclosures may be provided prospectively or retrospectively. The amendments are effective for annual reporting periods beginning after December 15, 2026, and interim periods within annual reporting periods beginning after December 15, 2027. Early adoption is permitted. The Company will provide the additional required disclosures upon adoption.
v3.25.4
Revenue
12 Months Ended
Dec. 31, 2025
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. Refer to Note 22 for the Company’s 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 with fixed pricing terms. 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,
202520242023
Export met coal revenues$1,500,265 $2,237,571 $2,412,960 
Export thermal coal revenues56,821 72,206 126,108 
Total export coal revenues$1,557,086 $2,309,777 $2,539,068 
Domestic met coal revenues$530,195 $608,971 $865,667 
Domestic thermal coal revenues35,324 27,831 51,895 
Total domestic coal revenues$565,519 $636,802 $917,562 
Total met coal revenues$2,030,460 $2,846,542 $3,278,627 
Total thermal coal revenues92,145 100,037 178,003 
Total coal revenues$2,122,605 $2,946,579 $3,456,630 


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, 2025.
20262027202820292030Total
Estimated coal revenues (1)
$83,560 $12,300 $— $— $— $95,860 
(1)     Amounts include only estimated coal revenues associated with contracts with customers with fixed pricing with original expected duration of more than one year. The Company has elected not to disclose the aggregate amount of the transaction price allocated to the performance obligations that are unsatisfied (or partially unsatisfied) as of the end of the reporting period for performance obligations with either of the following conditions: 1) the remaining performance obligation is part of a contract that has an original expected duration of one year or less; or 2) the remaining performance obligation has variable consideration that is allocated entirely to a wholly unsatisfied performance obligation.
v3.25.4
Accumulated Other Comprehensive Loss
12 Months Ended
Dec. 31, 2025
Equity [Abstract]  
Accumulated Other Comprehensive Loss Accumulated Other Comprehensive Loss
The following tables summarize the changes to accumulated other comprehensive loss during the years ended December 31, 2025, 2024, and 2023:
Balance January 1, 2025Other comprehensive loss before reclassificationsAmounts reclassified from accumulated other comprehensive lossBalance December 31, 2025
Employee benefit costs$(50,082)$(14,766)$4,415 $(60,433)
Balance January 1, 2024
Other comprehensive loss before reclassificationsAmounts reclassified from accumulated other comprehensive loss
Balance December 31, 2024
Employee benefit costs$(40,587)$(12,963)$3,468 $(50,082)
Balance January 1, 2023
Other comprehensive loss before reclassificationsAmounts reclassified from accumulated other comprehensive loss
Balance December 31, 2023
Employee benefit costs$(12,162)$(26,617)$(1,808)$(40,587)
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, 2025, 2024, and 2023:
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,
202520242023
Employee benefit costs:
Amortization of actuarial loss (gain) (1)
$5,645 $4,431 $(2,324)
Miscellaneous expense, net
Settlement (1)
— 26 — 
Miscellaneous expense, net
Total before income tax$5,645 $4,457 $(2,324)
Income tax (expense) benefit(1,230)(989)516 Income tax benefit (expense)
Total, net of income tax$4,415 $3,468 $(1,808)
(1)     These accumulated other comprehensive loss components are included in the computation of net periodic benefit costs (credits) for certain employee benefit plans. Refer to Note 17.
v3.25.4
Net (Loss) Income Per Share
12 Months Ended
Dec. 31, 2025
Earnings Per Share [Abstract]  
Net (Loss) Income Per Share Net (Loss) Income Per Share
The number of shares of common stock used to calculate basic net (loss) income 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 of common stock used to calculate diluted net (loss) income per common share is based on the number of common shares used to calculate basic net (loss) income per common share plus the effect of potentially dilutive securities outstanding during the period, which is determined by the application of the treasury stock method. 

When applying the treasury stock method, anti-dilution generally occurs when the exercise prices or unrecognized compensation cost per share of common stock are higher than the Company’s average price per share of common stock during an applicable period. For the years ended December 31, 2025, 2024, and 2023, respectively, 0, 159, and 1,240 securities were excluded from the computation of dilutive net income per common share because they would have been anti-dilutive.

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, 2025, the weighted average share impact of securities excluded from the shares due to the Company incurring a net loss for the period was 36,761.

The following table presents the net (loss) income per common share for the years ended December 31, 2025, 2024, and 2023:

Year Ended December 31,
202520242023
Basic
Net (loss) income$(61,687)$187,579 $721,956 
Weighted average common shares outstanding - basic12,996,148 13,013,469 14,106,466 
Net (loss) income per common share - basic$(4.75)$14.41 $51.18 
Diluted
Weighted average common shares outstanding - basic12,996,148 13,013,469 14,106,466 
Diluted effect of warrants— — 81,352 
Diluted effect of stock options— — 1,400 
Diluted effect of other stock-based instruments— 121,337 453,638 
Weighted average common shares outstanding - diluted12,996,148 13,134,806 14,642,856 
Net (loss) income per common share - diluted$(4.75)$14.28 $49.30 
v3.25.4
Inventories, net
12 Months Ended
Dec. 31, 2025
Inventory Disclosure [Abstract]  
Inventories, net Inventories, net
Inventories, net consisted of the following: 
December 31,
 20252024
Raw coal$41,665 $39,689 
Saleable coal81,919 65,129 
Materials, supplies and other, net 69,416 64,451 
Total inventories, net$193,000 $169,269 
v3.25.4
Capital Stock
12 Months Ended
Dec. 31, 2025
Equity [Abstract]  
Capital Stock Capital Stock
Share Repurchase Program

The total authorization to repurchase the Company’s stock under the existing common share repurchase program adopted by the Company’s Board of Directors (the “Board”) on March 4, 2022 is $1,500,000. Share repurchases may be made from time to time through open market transactions, block trades, tender offers, or otherwise, and the program has no expiration date. The share repurchase program does not obligate the Company to acquire any particular amount of common stock or to acquire shares on any particular timetable, and the program may be suspended at any time at the Company’s discretion. Repurchases under the program are subject to market and business conditions, available liquidity, the Company’s cash needs, restrictions under agreements or obligations, legal or regulatory requirements or restrictions and other relevant factors. As of December 31, 2025, the Company had repurchased an aggregate of 6,878,449 shares under the program for an aggregate purchase price of approximately $1,138,916 (comprised of $1,138,709 of share repurchases and $207 of related fees). The Company has also accrued a stock repurchase excise tax of $327 related to the share repurchase program as of December 31, 2025, which is recorded in treasury stock at cost.

Dividend Program

On May 3, 2022, the Board adopted a dividend policy. Pursuant to this policy, the Board paid quarterly dividends during the years ended December 31, 2022 and 2023. In addition, pursuant to the terms of certain stock-based compensation awards under the Company’s Management Incentive Plan (the “MIP”) and Long-Term Incentive Plan (the “LTIP”), dividend equivalent amounts for each quarterly dividend will become payable at various vesting dates with respect to each underlying outstanding award. On August 2, 2023, the Board determined to end the Company’s fixed dividend program following the quarterly dividend declared and paid in the fourth quarter of 2023 and to focus instead at that time on the Company’s share repurchase program. The decision to declare and pay cash dividends will be made by the Board and will depend on the Company’s earnings, financial condition and other relevant factors.

Warrants

On July 26, 2016, the Company issued 810,811 warrants, which were classified as equity instruments. Pursuant to the underlying warrant agreement (refer to Note 2), the exercise price was adjusted from $45.086 per share to $44.972 per share as of the March 15, 2023 dividend record date and to $44.820 per share as of the June 15, 2023 dividend record date, while the warrant share number remained unchanged at 1.20. At 5:00 pm Eastern time on July 26, 2023 the Company’s Series A Warrants expired pursuant to their terms.
As of December 31, 2023, no warrants remained outstanding as the warrants expired during the third quarter of 2023. For the year ended December 31, 2023, the Company issued 169,028 shares of common stock resulting from exercises of its warrants and, pursuant to the terms of the underlying warrant agreement, withheld 20,139 of the issued shares in satisfaction of the warrant exercise price and in lieu of fractional shares, which were subsequently reclassified as treasury stock in the amount of $2,368.
v3.25.4
Property, Plant, and Equipment, net
12 Months Ended
Dec. 31, 2025
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,
 20252024
Plant and mining equipment$1,050,261 $1,024,467 
Mine development241,154 199,419 
Land33,089 33,180 
Office equipment, software and other5,861 5,603 
Construction in progress65,602 39,462 
Total property, equipment and mine development costs$1,395,967 $1,302,131 
Less accumulated depreciation and amortization(774,101)(667,260)
Total property, plant, and equipment, net$621,866 $634,871 
Included in plant and mining equipment are assets under financing leases totaling $15,780 and $10,963 with accumulated depreciation of $4,827 and $6,529 as of December 31, 2025 and 2024, respectively.
Depreciation and amortization expense associated with property, plant, equipment and non-mineral asset retirement obligation assets, net, was $152,266, $139,256, and $112,925 for the years ended December 31, 2025, 2024, and 2023 respectively.

Depreciation expense for the years ended December 31, 2025, 2024, and 2023 includes an expense of $3,092, a credit of ($3,747), and an expense of $7,343, respectively, related to revisions to asset retirement obligations. Refer to Note 14 for further disclosures related to asset retirement obligations.
As of December 31, 2025, the Company had unconditional purchase obligations for approximately $9,655 of new equipment purchase commitments expected to be acquired at various dates in 2026.
v3.25.4
Other Non-Current Assets
12 Months Ended
Dec. 31, 2025
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,
20252024
Advanced mining royalties$8,975 $9,482 
Long-term deposits4,792 4,953 
Equity method investments53,850 41,072 
Workers’ compensation receivables30,365 34,075 
Goodwill11,124 11,124 
Other10,596 10,886 
Total other non-current assets$119,702 $111,592 
v3.25.4
Equity Method Investments
12 Months Ended
Dec. 31, 2025
Equity Method Investments and Joint Ventures [Abstract]  
Equity Method Investments Equity Method Investments
The Company holds a 65% partnership interest in Dominion Terminal Associates LLP (“DTA”) which operates a ground storage-to-vessel coal transloading facility in Newport News, Virginia for use by its partners. As the Company shares power with its minority partner through equal management committee representation, the Company does not control DTA. Under the terms of operating and throughput and handling agreements, each partner is charged its share of cash operating costs in exchange for the right to use the facility’s loading capacity and is required to make periodic cash advances to fund such costs.
The Company’s equity method investees do not have long-term debt obligations and the Company is not contingently obligated to make any future financing-related payments with respect to its equity method investees. Refer to Note 20 for information related to the Company’s commitment to fund certain infrastructure and equipment upgrades.
v3.25.4
Leases
12 Months Ended
Dec. 31, 2025
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, 2025, 2024, and 2023 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, 2025, 2024, and 2023.

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, 2025, the Company does not intend to exercise any termination options on existing leases.

As of December 31, 2025 and 2024, the Company had the following right-of-use assets and lease liabilities within the Company’s Consolidated Balance Sheets:
December 31, 2025December 31, 2024
AssetsBalance Sheet Classification
Financing lease assetsProperty, plant, and equipment, net$10,953 $4,434 
Operating lease right-of-use assetsOther non-current assets5,337 3,564 
Total lease assets$16,290 $7,998 
LiabilitiesBalance Sheet Classification
Financing lease liabilities - currentCurrent portion of long-term debt$2,108 $1,332 
Operating lease liabilities - currentAccrued expenses and other current liabilities690 597 
Financing lease liabilities - long-termLong-term debt7,452 2,666 
Operating lease liabilities - long-termOther non-current liabilities4,647 2,967 
Total lease liabilities$14,897 $7,562 

Total lease costs and other lease information for the years ended December 31, 2025, 2024, and 2023 included the following:
Year Ended December 31,
202520242023
Lease cost (1)
Financing lease cost:
     Amortization of leased assets$1,577 $1,513 $1,444 
     Interest on lease liabilities418 571 651 
Operating lease cost995 1,012 1,127 
Short-term lease cost1,316 1,181 1,315 
     Total lease cost$4,306 $4,277 $4,537 
(1)     The Company had no variable lease costs or sublease income for the years ended December 31, 2025, 2024, and 2023.
Year Ended December 31,
202520242023
Other information
Cash paid for amounts included in the measurement of lease liabilities$5,261 $4,042 $4,571 
     Operating cash flows from financing leases$418 $571 $651 
     Operating cash flows from operating leases$2,310 $2,193 $2,443 
     Financing cash flows from financing leases$2,533 $1,278 $1,477 
Right-of-use assets obtained in exchange for new financing lease liabilities$7,949 $— $1,891 
Right-of-use assets obtained in exchange for new operating lease liabilities$2,316 $103 $206 
Lease Term and Discount Rate
Weighted-average remaining lease term in years - financing leases5.004.605.10
Weighted-average remaining lease term in years - operating leases6.505.506.30
Weighted-average discount rate - financing leases8.1 %12.2 %12.3 %
Weighted-average discount rate - operating leases9.6 %11.5 %11.4 %

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, 2025:
Financing LeasesOperating Leases
Lease cost
2026$2,734 $1,234 
20272,243 1,214 
20281,956 1,195 
20291,956 1,179 
20301,956 1,132 
Thereafter814 1,238 
Total future minimum lease payments$11,659 $7,192 
Imputed interest(2,099)(1,855)
Present value of future minimum lease payments$9,560 $5,337 
As of December 31, 2025, 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, 2025, 2024, and 2023 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, 2025, 2024, and 2023.

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, 2025, the Company does not intend to exercise any termination options on existing leases.

As of December 31, 2025 and 2024, the Company had the following right-of-use assets and lease liabilities within the Company’s Consolidated Balance Sheets:
December 31, 2025December 31, 2024
AssetsBalance Sheet Classification
Financing lease assetsProperty, plant, and equipment, net$10,953 $4,434 
Operating lease right-of-use assetsOther non-current assets5,337 3,564 
Total lease assets$16,290 $7,998 
LiabilitiesBalance Sheet Classification
Financing lease liabilities - currentCurrent portion of long-term debt$2,108 $1,332 
Operating lease liabilities - currentAccrued expenses and other current liabilities690 597 
Financing lease liabilities - long-termLong-term debt7,452 2,666 
Operating lease liabilities - long-termOther non-current liabilities4,647 2,967 
Total lease liabilities$14,897 $7,562 

Total lease costs and other lease information for the years ended December 31, 2025, 2024, and 2023 included the following:
Year Ended December 31,
202520242023
Lease cost (1)
Financing lease cost:
     Amortization of leased assets$1,577 $1,513 $1,444 
     Interest on lease liabilities418 571 651 
Operating lease cost995 1,012 1,127 
Short-term lease cost1,316 1,181 1,315 
     Total lease cost$4,306 $4,277 $4,537 
(1)     The Company had no variable lease costs or sublease income for the years ended December 31, 2025, 2024, and 2023.
Year Ended December 31,
202520242023
Other information
Cash paid for amounts included in the measurement of lease liabilities$5,261 $4,042 $4,571 
     Operating cash flows from financing leases$418 $571 $651 
     Operating cash flows from operating leases$2,310 $2,193 $2,443 
     Financing cash flows from financing leases$2,533 $1,278 $1,477 
Right-of-use assets obtained in exchange for new financing lease liabilities$7,949 $— $1,891 
Right-of-use assets obtained in exchange for new operating lease liabilities$2,316 $103 $206 
Lease Term and Discount Rate
Weighted-average remaining lease term in years - financing leases5.004.605.10
Weighted-average remaining lease term in years - operating leases6.505.506.30
Weighted-average discount rate - financing leases8.1 %12.2 %12.3 %
Weighted-average discount rate - operating leases9.6 %11.5 %11.4 %

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, 2025:
Financing LeasesOperating Leases
Lease cost
2026$2,734 $1,234 
20272,243 1,214 
20281,956 1,195 
20291,956 1,179 
20301,956 1,132 
Thereafter814 1,238 
Total future minimum lease payments$11,659 $7,192 
Imputed interest(2,099)(1,855)
Present value of future minimum lease payments$9,560 $5,337 
As of December 31, 2025, the Company had no leases with future commencement dates that will create significant rights or obligations for the Company.
v3.25.4
Accrued Expenses and Other Current Liabilities
12 Months Ended
Dec. 31, 2025
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,
 20252024
Wages and benefits$46,687 $48,642 
Workers’ compensation 8,880 9,444 
Black lung 12,329 11,209 
Taxes other than income taxes26,315 27,995 
Asset retirement obligations22,632 29,938 
Freight accrual12,018 16,144 
Other 6,917 8,188 
Total accrued expenses and other current liabilities$135,778 $151,560 
v3.25.4
Long-Term Debt
12 Months Ended
Dec. 31, 2025
Debt Disclosure [Abstract]  
Long-Term Debt Long-Term Debt
Long-term debt consisted of the following: 
December 31,
 20252024
Notes payable and other$3,856 $1,786 
Financing leases9,560 3,998 
Total long-term debt $13,416 $5,784 
Less current portion(3,575)(2,916)
Long-term debt, net of current portion$9,841 $2,868 

ABL Agreement

On October 27, 2023, the Company terminated its existing Second Amended and Restated Asset-Based Revolving Credit Agreement dated December 6, 2021 and along with certain of its directly and indirectly owned subsidiaries (the “Borrowers”) entered into a new Credit Agreement (the “ABL Agreement”) with Regions Bank, as lender, swingline lender, LC issuer, administrative agent, collateral agent, and lead arranger, along with ServisFirst Bank and Texas Capital Bank, as joint lead arrangers and the other lenders party thereto. In connection with the termination, the Company recorded a loss on extinguishment of debt of $2,753 related to the write-off of unamortized debt issuance costs for and fees paid to exiting lenders. The ABL Agreement included an asset-based revolving credit facility (the “ABL Facility”) which allowed the Company to borrow cash or obtain LCs, on a revolving basis, in an aggregate amount of up to $155,000.

On May 6, 2025, the Company amended and extended the ABL Agreement to increase the size of the ABL Facility to $225,000. In addition, the Company may request an increase to the capacity of the facility of up to an additional $75,000 provided that $25,000 shall be solely for the purpose of providing additional availability to obtain cash collateralized LCs. Availability under the ABL Facility is calculated monthly and fluctuates based on qualifying amounts of coal inventory, trade accounts receivable, and in certain circumstances specified amounts of cash. Following the amendment, the ABL Facility matures on May 4, 2029. The ABL Facility is guaranteed by substantially all of Alpha’s directly and indirectly owned subsidiaries that are not Borrowers (the “Guarantors”) and is secured by all or substantially all assets of the Borrowers and Guarantors.

Under the amended terms of the ABL Facility, LC fees will be calculated at a rate of 2.25%, 2.50% or 2.75% depending on the level of available capacity under the facility, plus a fronting fee of 0.25%. Any future borrowings will bear interest based on the character of the loan (defined as either a “Term Secured Overnight Financing Rate Loan” (or “Term SOFR Loan”) or a “Base Rate Loan”). Term SOFR Loans bear interest at a rate equal to Term SOFR, plus 0.10% SOFR Adjustment plus an applicable rate of 2.25%, 2.50% or 2.75%, and Base Rate Loans bear interest at a rate equal to the Base Rate plus an applicable margin rate of 1.25%, 1.50% or 1.75%, in each case, depending on the level of available capacity under the facility at the time
of the loan. The Company may elect the character and interest period for each loan. All amounts borrowed may be repaid prior to maturity without penalty. A commitment fee of 0.375% will be charged on any unused capacity. As of December 31, 2025 and December 31, 2024, the Company had no amounts borrowed and $41,254 and $42,149 LCs outstanding under the ABL Facility, respectively.

The ABL agreement limits the Company’s ability to make certain restricted payments, including the payment of cash dividends and the repurchase of equity shares under its share repurchase program, if the level of cash it maintains at Regions Bank falls below $100,000. The ABL Agreement also contains negative and affirmative covenants and requires the Company to maintain minimum Liquidity, as defined in the ABL Agreement, of $75,000. As of December 31, 2025, the Company’s cash balance at Regions Bank exceeded the $100,000 threshold and the Company is in compliance with all covenants under the ABL Agreement.

Future Maturities

Future maturities of long-term debt as of December 31, 2025 are as follows: 
2026$3,575 
20273,055 
20282,600 
20291,667 
20301,795 
After 2030724 
Total long-term debt$13,416 
v3.25.4
Asset Retirement Obligations
12 Months Ended
Dec. 31, 2025
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, 2025 and 2024:
Total asset retirement obligations at December 31, 2023$205,424 
Accretion for the period 25,050 
Sites added during the period5,381 
Revisions in estimated cash flows (1)
12,414 
Expenditures for the period(28,526)
Total asset retirement obligations at December 31, 2024$219,743 
Accretion for the period22,126 
Sites added during the period 475 
Revisions in estimated cash flows 61 
Expenditures for the period(15,028)
Total asset retirement obligations at December 31, 2025$227,377 
Less current portion (2)
(22,632)
Long-term portion$204,745 
(1)    The revisions in estimated cash flows for the year ended December 31, 2024 resulted primarily from a decrease in the discount rate and changes in mine plans.
(2)    Included within Accrued expenses and other current liabilities on the Company’s Consolidated Balance Sheets. Refer to Note 12.
v3.25.4
Fair Value of Financial Instruments and Fair Value Measurements
12 Months Ended
Dec. 31, 2025
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, restricted cash, deposits, trade accounts payable, notes payable and other, financing leases, and accrued expenses and other current liabilities approximate fair value as of December 31, 2025 and 2024 due to the short maturity of these instruments.
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, 2025 and 2024. 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, 2025
Total Fair ValueQuoted Prices in Active Markets (Level 1)Significant Other Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Trading securities (1)
$83,938 $— $83,938 $— 
(1)     Includes $49,582 classified as Short-term investments and $34,356 classified as Long-term restricted investments on the Company’s Consolidated Balance Sheets.

 December 31, 2024
Total Fair ValueQuoted Prices in Active Markets (Level 1)Significant Other Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Trading securities (1)
$43,131 $— $43,131 $— 
(1)     Classified as Long-term restricted investments on the Company’s Consolidated Balance Sheets.

The following methods and assumptions were used to estimate the fair values of the assets and liabilities in the tables above:
Level 2 Fair Value Measurements
Trading Securities - Typically includes U.S. government securities. The fair values 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.
v3.25.4
Income Taxes
12 Months Ended
Dec. 31, 2025
Income Tax Disclosure [Abstract]  
Income Taxes Income Taxes
Significant components of income tax (benefit) expense were as follows:
Year Ended December 31,
202520242023
Current tax (benefit) expense:
Federal$(1,977)$17,219 $80,254 
State(55)389 3,527 
Total current$(2,032)$17,608 $83,781 
Deferred tax (benefit) expense:
Federal$(22,301)$3,868 $35,824 
State(1,439)1,695 3,898 
Total deferred $(23,740)$5,563 $39,722 
Total income tax (benefit) expense:
Federal$(24,278)$21,087 $116,078 
State(1,494)2,084 7,425 
Total$(25,772)$23,171 $123,503 

Materially all of the Company’s (loss) income before income taxes and associated income tax (benefit) expense arises from its domestic operations within the United States.

A reconciliation of statutory federal income tax expense on income to the actual income tax expense is as follows:
Year Ended December 31, 2025Year Ended December 31, 2024Year Ended December 31, 2023
AmountPercentAmountPercentAmountPercent
U.S. federal statutory tax rate$(18,366)21.0 %$44,258 21.0 %$177,547 21.0 %
State and local income taxes, net of federal income tax effect (1)
(1,181)1.4 %1,647 0.8 %5,866 0.7 %
Effect of cross-border tax laws
Foreign-derived intangible income deduction— — %(2,718)(1.3)%(24,291)(2.9)%
Change in valuation allowances(43,361)49.6 %(341)(0.2)%(3,045)(0.4)%
Nontaxable or nondeductible items
Percentage depletion allowance(9,586)11.0 %(20,245)(9.6)%(36,685)(4.3)%
Non-deductible compensation2,691 (3.1)%28,320 13.4 %9,934 1.2 %
Stock-based compensation(1,124)1.3 %(28,710)(13.6)%(6,968)(0.8)%
Other, net866 (1.0)%907 0.4 %653 0.1 %
Other adjustments
Capital loss expiration43,261 (49.5)%— — %— — %
Provision-to-return adjustment1,045 (1.2)%188 0.1 %683 0.1 %
Other, net(17)— %(135)— %(191)(0.1)%
Effective tax rate$(25,772)29.5 %$23,171 11.0 %$123,503 14.6 %
(1)    State taxes in Illinois, Virginia, and West Virginia made up the majority (greater than 50 percent) of the tax effect in this category.
The amounts of cash taxes paid (net of refunds received) by the Company are as follows:
Year Ended December 31,
202520242023
US federal$— $11,000 $75,700 
US state and local
Kentucky(174)(1,308)(8)
Tennessee125 351 45 
Virginia2,225 (1,756)3,037 
Other(58)92 417 
Total$2,118 $8,379 $79,191 

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,
20252024
Deferred tax assets:
  Asset retirement obligations$49,773 $47,561 
  Reserves and accruals not currently deductible9,107 9,021 
  Workers’ compensation and black lung obligations41,659 38,538 
Pension obligations17,336 18,246 
Net operating loss carryforwards43,323 31,810 
Capital loss carryforwards— 45,072 
  Other 8,046 10,878 
     Gross deferred tax assets169,244 201,126 
Less valuation allowance(3,159)(48,734)
     Deferred tax assets$166,085 $152,392 
Deferred tax liabilities:
Property, plant and mineral reserves$(161,917)$(174,031)
  Acquired intangibles(6,250)(7,371)
  Prepaid expenses(3,648)(3,900)
  Other (1,616)(1,060)
     Total deferred tax liabilities(173,431)(186,362)
     Net deferred tax liabilities$(7,346)$(33,970)


Changes in the valuation allowance were as follows:
Year Ended December 31,
202520242023
Valuation allowance beginning of period$48,734 $48,143 $53,801 
(Decrease) increase in valuation allowance recorded to income tax expense (45,575)591 (5,658)
Valuation allowance end of period$3,159 $48,734 $48,143 

At December 31, 2025, the Company has recorded a deferred tax asset of $33,755 for federal net operating loss carryforwards, which represents the tax-effected amount of net operating loss carryforwards mathematically available for
utilization prior to statutory expiration. Underlying this deferred tax asset are approximately $11,000 of gross federal net operating loss carryforwards that are subject to an annual Internal Revenue Code Section 382 limitation of approximately $1,000, approximately $97,000 of gross federal net operating loss carryforwards that are subject to an annual Internal Revenue Code Section 382 limitation of approximately $17,500, and approximately $53,000 of gross federal net operating loss carryforwards that are not subject to an annual Internal Revenue Code Section 382 limitation. The gross federal net operating loss carryforwards of approximately $11,000 and $97,000 were generated prior to 2018 and will expire between years 2035 and 2037. The gross federal net operating loss carryforward of approximately $53,000 was generated in 2025 and is not subject to an expiration period. A valuation allowance is recorded against certain state net operating loss carryforwards to the extent the Company is unable to support their realization.

The Company has no liability for uncertain tax positions for the years ended December 31, 2025, 2024, and 2023.

The Company’s policy is to classify interest and penalties related to uncertain tax positions as part of income tax expense. The Company did not accrue any interest and penalties relating to uncertain positions on its Consolidated Statements of Operations for the years ended December 31, 2025, 2024, and 2023. Similarly, the Company had no balances for accrued interest and penalties on its Consolidated Balance Sheets as of December 31, 2025 and 2024.

As of December 31, 2025, tax years 2022 – 2025 remain open to federal and state examination.

On July 4, 2025, legislation commonly referred to as the “One Big Beautiful Bill Act” (“OBBBA”) was signed into law. Changes made by the OBBBA include the reinstatement of 100% bonus depreciation, the reinstatement of immediate expensing for domestic research and experimentation costs, changes to the calculation of the foreign-derived intangible income deduction and the interest expense limitation, and the addition of metallurgical coal to the list of “applicable critical minerals” for purposes of the Section 45X credit. The Section 45X credit (also known as the advanced manufacturing production credit), as amended, provides a refundable tax credit equal to 2.5% of the production costs for metallurgical coal produced during tax years 2026 and 2029. The Company incorporated the effects of the OBBBA in its income tax provision for the year ended December 31, 2025.

On August 16, 2022, legislation commonly referred to as the Inflation Reduction Act of 2022 (“IRA”) was signed into law. Among other provisions, the IRA enacted a 15% corporate alternative minimum tax and a 1% excise tax on repurchases of corporate stock for tax years beginning after December 31, 2022. The Company determined that it is not subject to the corporate alternative minimum tax for the years ended December 31, 2025, 2024 and 2023. Refer to Note 7 for information on the excise tax on repurchases of the Company’s corporate stock.
v3.25.4
Employee Benefit Plans
12 Months Ended
Dec. 31, 2025
Compensation Related Costs [Abstract]  
Employee Benefit Plans Employee Benefit Plans
The Company provides several types of benefits for its employees, including a defined benefit and defined contribution pension plan, 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 cost (credit) other than the service cost component for black lung are included in the line item Miscellaneous expense, net, in the Consolidated Statements of Operations.

Company Administered Defined Benefit Pension Plan

In connection with the Merger, the Company assumed three qualified non-contributory defined benefit pension plans, which covered certain salaried and non-union hourly employees. The qualified non-contributory defined benefit pension plans were collectively referred to as the “Pension Plans.” Effective as of December 31, 2023, the assets and liabilities of the Pension Plans were merged into one qualified non-contributory defined benefit pension plan (“Pension Plan”). Benefits are frozen under the Pension Plan. 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. The Pension Plan 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 Plan are made as recommended by consulting actuaries based upon the ERISA funding standards. Projected contributions are based on the latest available data and include the impact of the funding relief granted by the American Rescue Plan Act (“ARPA”) and the application of the interest rate stabilization guidance under ARPA.
Plan assets consist of equity securities, fixed income funds, commingled short-term funds, private equity funds, a guaranteed insurance contract, and cash and cash equivalents.

The following tables set forth the Pension Plan’s accumulated benefit obligation, fair value of plan assets and funded status for the years ended December 31, 2025 and 2024.
Year Ended December 31,
20252024
Change in benefit obligations:
Accumulated benefit obligation at beginning of period:$451,976 $478,366 
Interest cost 23,254 23,672 
Actuarial loss (gain)13,487 (17,715)
Benefits paid(31,312)(32,347)
Accumulated benefit obligation at end of period$457,405 $451,976 
Change in fair value of plan assets:
Fair value of plan assets at beginning of period$351,379 $376,458 
Actual return on plan assets33,055 (5,052)
Employer contributions16,966 12,320 
Benefits paid(31,312)(32,347)
Fair value of plan assets at end of period$370,088 $351,379 
Funded status$(87,317)$(100,597)
Accrued benefit cost at end of period (1)
$(87,317)$(100,597)
(1)     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, 2025 and 2024:
December 31,
20252024
Net actuarial loss$31,053 $32,545 

The following table details the components of net periodic benefit cost:
Year Ended December 31,
202520242023
Interest cost$23,254 $23,672 $23,973 
Expected return on plan assets(19,673)(20,913)(21,996)
Amortization of net actuarial loss1,597 1,764 730 
Net periodic benefit cost$5,178 $4,523 $2,707 

Other changes in plan assets and benefit obligation recognized in other comprehensive (loss) income are as follows:
Year Ended December 31,
202520242023
Actuarial loss (1)
$105 $8,250 $14,106 
Amortization of net actuarial loss(1,597)(1,764)(730)
Total recognized in other comprehensive (loss) income$(1,492)$6,486 $13,376 
(1) For the year ended December 31, 2024, the actuarial loss was primarily attributable to lower than expected return on plan assets and an annual census data actuarial revaluation of pension obligations, partially offset by an increase in the weighted-average discount rate actuarial assumption used in determining the benefit obligation.

The following table presents information applicable to plans with accumulated benefit obligations in excess of plan assets:
Year Ended December 31,
20252024
Projected benefit obligation$457,405 $451,976 
Accumulated benefit obligation$457,405 $451,976 
Fair value of plan assets$370,088 $351,379 

The weighted-average actuarial assumption used in determining the benefit obligation as of December 31, 2025 and 2024 was as follows: 
December 31,
20252024
Discount rate5.44 %5.65 %

The weighted-average actuarial assumptions used to determine net periodic benefit cost (credit) for the years ended December 31, 2025, 2024, and 2023 were as follows: 
Year Ended December 31,
202520242023
Discount rate for benefit obligation5.65 %5.12 %5.42 %
Discount rate for interest cost5.33 %4.99 %5.27 %
 Expected long-term rate of return on plan assets (1)
5.70 %5.70 %6.20 %
(1)     During the three months ended June 30, 2024, the Company updated the 2024 expected long-term rate of return on plan assets from 6.20% to 5.70% based on a weighted basis of the beginning and more recently assumed rate as the pension plan’s target allocation was updated to 50% equity securities and 50% fixed income funds in the interim period.

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 Plan is established each year in consultation with the plan’s actuaries and outside investment advisors. This rate is determined by taking into consideration the Pension Plan’s target asset allocation, expected long-term rates of return on each major asset class by reference to long-term historic ranges, and inflation assumptions. For the determination of net periodic benefit cost in 2026, the Company will utilize an expected long-term rate of return on plan assets of 5.70%.

Assets of the Pension Plan 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 2026 and the actual asset allocation as reported at December 31, 2025 are as follows:
Target Allocation Percentages 2026Percentage of Plan Assets 2025
Equity securities50.0 %50.0 %
Fixed income funds50.0 %44.0 %
Other— %6.0 %
Total100.0 %100.0 %

The asset allocation targets have been set with the expectation that the Pension Plan’s assets will fund the expected liability within an appropriate level of risk. In determining the appropriate target asset allocations, the Benefits Committee considers the demographics of the Pension Plan’s participants, the funded status of the plan, the Company’s contribution philosophy, the
Company’s business and financial profile, and other associated risk factors. The Pension Plan’s 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 the Pension Plan.

The Company contributed $16,966 to the Pension Plan during the year ended December 31, 2025. In 2026, the Company expects to contribute $23,108 of estimated minimum required contributions to the Pension Plan for the 2025 and 2026 plan years.

The following represents expected future pension benefit payments for the next ten years:
2026$31,937 
202731,822 
202831,526 
202931,236 
203030,964 
2031-2035152,532 
$310,017 

The fair values of the Company’s Pension Plan’s assets as of December 31, 2025, by asset category are as follows:
Asset Category
Total
Level 1Level 2Level 3
Assets Measured at NAV (1)
Equity securities:
ETF funds
$97,401 $97,401 $— $— $— 
Mutual funds87,179 87,179 — — — 
Fixed income funds:
Corporate bonds
92,076 — 92,076 — — 
U.S. government securities68,270 — 68,270 — — 
Commingled short-term fund (2)
1,196 — 1,196 — — 
Private equity funds404 — — — 404 
Other types of investments:
Guaranteed insurance contract12,488 — — 12,488 — 
Total$359,014 $184,580 $161,542 $12,488 $404 
Cash & cash equivalents (3)
8,931 
Receivable (4)
2,143 
Total plan assets$370,088 
(1)    In accordance with ASU 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.
(2)    This fund contains cash and highly liquid short-term investments in a collective investment fund.
(3)    Represents cash on deposit that has FDIC insurance, which approximates fair value.
(4)    Receivable for investments sold at December 31, 2025, which approximates fair value.
The fair values of the Company’s Pension Plan’s assets as of December 31, 2024, by asset category are as follows:
Asset Category
Total
Level 1Level 2Level 3
Assets Measured at NAV (1)
Equity securities:
Multi-asset fund
$170,829 $— $170,829 $— $— 
Fixed income funds:
Bond fund
165,100 — 165,100 — — 
Commingled short-term fund (2)
1,269 — 1,269 — — 
Private equity funds
448 — — — 448 
Other types of investments:
Guaranteed insurance contract12,488 — — 12,488 — 
Total$350,134 $— $337,198 $12,488 $448 
Receivable (3)
1,245 
Total plan assets$351,379 
(1)    In accordance with ASU 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.
(2)    This fund contains cash and highly liquid short-term investments in a collective investment fund.
(3)    Receivable for investments sold at December 31, 2024, which approximates fair value.

Changes in Level 3 plan assets for the period ended December 31, 2024 were as follows:
Level 3
Guaranteed Insurance Contract
Beginning balance, December 31, 2023$12,230 
Actual return on plan assets:
Relating to assets still held at the reporting date524 
Purchases, sales and settlements(266)
Ending balance, December 31, 2024$12,488 

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 certain 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 reinsurance company, the prepaid insurance amounts will be reduced by a corresponding amount. In 2025, the reinsurance company transferred its obligations to a new reinsurance company.

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, 2025, 2024 and 2023 was $8,113, $9,461, and $10,676, respectively.

Workers’ Compensation

The table below presents workers’ compensation amounts recognized in the Consolidated Balance Sheets:
December 31,
20252024
Current liabilities$8,880 $9,444 
Long-term liabilities72,685 79,897 
Total liabilities$81,565 $89,341 
Less expected insurance receivable (1)
(31,947)(35,891)
Workers’ compensation obligations, net of expected insurance receivables$49,618 $53,450 
(1)     Included within Prepaid expenses and other current assets and Other non-current assets in the Consolidated Balance Sheets.

Workers’ compensation expense (credit) for high-deductible insurance plans for the years ended December 31, 2025, 2024, and 2023 was $4,385, ($1,758), and ($271), respectively, included within Cost of coal sales in the Consolidated Statements of Operations.
Black Lung

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, 2025 and 2024:
Year Ended December 31,
20252024
Change in benefit obligation:
Accumulated benefit obligation at beginning of period$116,956 $109,871 
Service cost2,141 2,404 
Interest cost5,852 5,229 
Actuarial loss18,865 9,086 
Benefits paid(10,435)(9,634)
Accumulated benefit obligation at end of period$133,379 $116,956 
Change in fair value of plan assets:
Fair value of plan assets at beginning of period$2,683 $2,613 
Actual return on plan assets87 70 
Benefits paid(10,435)(9,634)
Employer contributions10,435 9,634 
Fair value of plan assets at end of period (1)
2,770 2,683 
Funded status$(130,609)$(114,273)
Accrued benefit cost at end of period$(130,609)$(114,273)
(1)     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.

The table below presents amounts recognized in the Consolidated Balance Sheets:
December 31,
20252024
Current liabilities$12,329 $11,209 
Long-term liabilities118,280 103,064 
Total liabilities$130,609 $114,273 

Gross amounts related to the black lung benefit obligations recognized in accumulated other comprehensive loss consisted of the following as of December 31, 2025 and 2024: 
December 31,
20252024
Net actuarial loss$33,341 $18,814 

The following table details the components of the net periodic benefit cost for the black lung benefit obligations:
Year Ended December 31,
202520242023
Service cost$2,141 $2,404 $2,051 
Interest cost5,852 5,229 4,660 
Expected return on plan assets(54)(52)(50)
Amortization of net actuarial loss (gain)4,305 2,884 (2,833)
Net periodic benefit cost$12,244 $10,465 $3,828 
Other changes in the black lung plan assets and benefit obligations recognized in other comprehensive income (loss) are as follows:
Year Ended December 31,
202520242023
Actuarial loss (1)
$18,832 $9,068 $19,995 
Amortization of net actuarial (loss) gain(4,305)(2,884)2,833 
Total recognized in other comprehensive income$14,527 $6,184 $22,828 
(1)     For the year ended December 31, 2025, the actuarial loss was primarily attributable to changes in demographic assumptions and a decrease in the weighted-average discount rate actuarial assumption used in determining the benefit obligations. For the year ended December 31, 2024, the actuarial loss was primarily attributable to an increase in new claimants and claims and changes in demographic assumptions, partially offset by an increase in the weighted-average discount rate actuarial assumption used in determining the benefit obligations.

The weighted-average assumptions related to black lung obligations used to determine the benefit obligation as of December 31, 2025 and 2024 were as follows: 
December 31,
20252024
Discount rate5.46 %5.66 %
Federal black lung income benefit trend rate2.50 %2.50 %
Federal black lung medical benefit trend rate5.00 %5.00 %

The weighted-average assumptions related to black lung benefit obligations used to determine net periodic benefit cost were as follows:
Year Ended December 31,
202520242023
Discount rate for benefit obligation5.66 %5.13 %5.42 %
Discount rate for service cost5.88 %5.31 %5.58 %
Discount rate for interest cost5.27 %4.98 %5.23 %
Federal black lung income benefit trend rate2.50 %2.50 %2.50 %
Federal black lung medical benefit trend rate5.00 %5.00 %5.00 %
Expected return on plan assets2.00 %2.00 %2.00 %

Estimated future cash payments related to black lung benefit obligations for the next 10 years ending after December 31, 2025 are as follows: 
Year ending December 31:
2026$12,329 
202712,200 
202811,960 
202911,769 
203011,703 
2031-2035
33,695 
$93,656 
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, 2025 and 2024, the postretirement life insurance benefit obligation was $8,259, including a current portion of $610, and $8,222, including a current portion of $600, 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, 2025, 2024, and 2023 were $6,578, $6,425, and $16,435, respectively.

During the fourth quarter of 2025, the Company paid a discretionary employer contribution under the Alpha Metallurgical Resources 401(k) Retirement Savings Plan (the “Plan”) equal to the 2% of the Plan participants’ annual salaries. During the first quarter of 2026, the Company’s matching contributions under the Plan were reinstated after being suspended due to weak market conditions during the second quarter of 2024.

Self-insured Medical Plan
The Company is self-insured for health benefit coverage for all of its active employees. During the years ended December 31, 2025, 2024, and 2023, the Company incurred total expenses of $106,551, $102,805, and $86,745, respectively, which primarily include claims processed and an estimate for claims incurred but not paid.
v3.25.4
Stock-Based Compensation Awards
12 Months Ended
Dec. 31, 2025
Share-Based Payment Arrangement [Abstract]  
Stock-Based Compensation Awards Stock-Based Compensation Awards
The MIP was authorized for the issuance of awards of up to 1,201,202 shares of common stock. Although management does not intend to grant any future awards under the MIP, there were 113,884 shares of common stock remaining for grant under the MIP as of December 31, 2025. 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, 2025, there were 765,333 shares of common stock available for grant under the LTIP.

The Company does not backdate or retroactively grant restricted stock units and generally schedules board and compensation committee meetings during the prior year. Further, the Company generally makes annual equity award grants to its directors and named executive officers at approximately the same times each year. The Company does not time equity awards to take advantage of the release of earnings or other major announcements by the Company, or market conditions.

As of December 31, 2025, the Company did not have outstanding awards of stock options, stock appreciation rights, or similar option-like instruments.

As of December 31, 2025, the Company had two types of stock-based awards outstanding: time-based restricted stock units and performance-based restricted stock units. Upon vesting and settlement or exercise of the stock-based awards outstanding, the Company issues authorized and unissued shares of the Company’s common stock to the recipient. Stock-based compensation expense totaled $13,640, $12,929, and $20,856 for the years ended December 31, 2025, 2024, and 2023, respectively. For the years ended December 31, 2025, 2024, and 2023, approximately 85%, 86%, and 95%, 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, 2025, the Company repurchased 26,519 shares of its common stock issued pursuant to awards under the MIP and LTIP for a total purchase amount of $5,155, or $194.39 average price paid per share. During the year ended December 31, 2024, the Company
repurchased 144,427 shares of its common stock issued pursuant to awards under the MIP and LTIP for a total purchase amount of $55,419, or $383.72 average price paid per share. During the year ended December 31, 2023, the Company repurchased 81,287 shares of its common stock issued pursuant to awards under the MIP and LTIP for a total purchase amount of $17,333, or $213.23 average price paid per share.

On November 8, 2023, the Company modified the terms of certain outstanding stock-based compensation awards previously granted to Mr. Stetson, the executive chair of the Board at the time of the modification. Pursuant to the terms of the modification, upon the completion of his service as executive chair as of the end of the day on December 31, 2023, and his appointment by the Board as non-executive chair of the Board effective as of January 1, 2024, the pro-rata vesting of his outstanding incentive awards was to be calculated as if his separation date were instead December 31, 2024. The modification resulted in total incremental compensation cost of $6,717 for the year ended December 31, 2023 and impacted the time-based restricted stock units and performance-based restricted stock units granted to him under the LTIP during the years ended December 31, 2023 and 2022. Awards held by other employees were not affected by the modification. As all modified awards are fully vested, there was no remaining compensation cost to be recognized as of December 31, 2023.

2025 Awards Granted

During the year ended December 31, 2025, the Company granted certain key employees and non-employee directors 50,335 time-based restricted stock units under the LTIP with a weighted average grant date fair value of $185.77 based on the Company’s closing stock price at the trading day before the date of the grant. Awards granted to key employees on January 22, 2025 will vest ratably over a three-year period from the date of the grant in accordance with the vesting schedule, subject to the participant’s continuous service with the Company through each applicable vesting date. Restricted stock units were also granted to non-employee directors on May 7, 2025, which will vest on the first to occur of (i) May 6, 2026, (ii) the director’s separation of service due to the director’s death or physical or mental incapacity to perform his or her usual duties, (iii) the director’s service as a member of the Board 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 (iv) a change in control.

Additionally, during the year ended December 31, 2025, the Company granted certain key employees 30,279 performance-based restricted stock units 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 the targeted performance level, 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 18,168 operational performance-based restricted stock units were valued based on the Company’s closing stock price on the trading day before the date of the grant and had a weighted average grant date fair value of $196.42. 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 12,111 relative total shareholder return performance-based restricted stock units were valued relative to the stock price performance of a comparator group and had weighted average grant date fair value based on a Monte Carlo simulation. Refer to the “Performance-Based Restricted Stock Units — Relative Performance-Based Restricted Stock Units” section below for further detail.

2024 Awards Granted

During the year ended December 31, 2024, the Company granted certain key employees and non-employee directors 25,734 time-based restricted stock units under the LTIP with a weighted average grant date fair value of $389.07 based on the Company’s closing stock price at the trading day before the date of the grant. Awards granted to key employees on January 24, 2024 will vest ratably over a three-year period from the date of the grant in accordance with the vesting schedule, subject to the participant’s continuous service with the Company through each applicable vesting date. Restricted stock units were also granted to two non-employee directors on February 29, 2024, which vested on May 2, 2024, and to multiple non-employee directors on May 2, 2024, which vested on May 1, 2025. Restricted stock units were also granted to Mr. Gorzynski effective with his appointment to chair of the Board on December 13, 2024, which vested on May 1, 2025.
Additionally, during the year ended December 31, 2024, the Company granted certain key employees 15,820 performance-based restricted stock units 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 the targeted performance level, 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 9,490 operational performance-based restricted stock units were valued based on the Company’s closing stock price on the trading day before the date of the grant and had a weighted average grant date fair value of $400.93. 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 6,330 relative total shareholder return performance-based restricted stock units were valued relative to the stock price performance of a comparator group and had weighted average grant date fair value based on a Monte Carlo simulation. Refer to the “Performance-Based Restricted Stock Units — Relative Performance-Based Restricted Stock Units” section below for further detail.

2023 Awards Granted

During the year ended December 31, 2023, the Company granted certain key employees and non-employee directors 35,018 time-based restricted stock units under the LTIP with a weighted average grant date fair value of $165.43 based on the Company’s closing stock price at the trading day before the date of the grant. Awards granted to key employees on January 25, 2023 will vest ratably over a three-year period from the date of the grant in accordance with the vesting schedule, subject to the participant’s continuous service with the Company through each applicable vesting date. Per the terms of the transition agreement between Mr. Stetson and the Company, dated November 18, 2022, relating to his service as the Company’s executive chair of the Board, and then as its non-executive chair, awards granted to Mr. Stetson were to vest pro-rata as of December 31, 2023, the last day of his service as the Company’s executive chair, reflecting his service through that date. The transition agreement was later amended as discussed above. Restricted stock units were also granted to a non-employee director on February 2, 2023, which vested on May 2, 2023, and to multiple non-employee directors on May 3, 2023, which vested on May 2, 2024.

Additionally, during the year ended December 31, 2023, the Company granted certain key employees 49,701 performance-based restricted stock units 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. Per the terms of the transition agreement between Mr. Stetson and the Company, dated November 18, 2022, relating to his service as the Company’s executive chair of the Board, and then as its non-executive chair, the awards granted to Mr. Stetson were to vest pro-rata as of December 31, 2023, the last day of his service as the Company’s executive chair, reflecting his service through that date. The transition agreement was later amended as discussed above. The performance-based restricted stock units have the potential to be earned from 0% to 200% of the targeted performance level, 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 29,816 operational performance-based restricted stock units were valued based on the Company’s closing stock price on the trading day before the date of the grant and had a weighted average grant date fair value of $171.07. 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. Of the 19,885 relative total shareholder return performance-based restricted stock units, 2,093 were valued based on the Company’s closing stock price on the trading day before the date of the grant and had a weighted average grant date fair value of $171.07, and 17,792 were valued relative to the stock price performance of a comparator group and had a weighted average grant date fair value based on a Monte Carlo simulation. Refer to the “Performance-Based Restricted Stock Units — Relative Performance-Based Restricted Stock Units” section below for further detail.
Time-Based Restricted Stock Units
Time-based restricted stock unit activity for the year ended December 31, 2025 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, 202443,330 $252.62 
Granted50,335 $185.77 
Vested (1)
(31,276)$175.00 
Forfeited(1,025)$249.49 
Non-vested shares outstanding at December 31, 202561,364 $237.40 
(1)     Includes 8,071 shares with deferred settlement pursuant to the award agreements.

As of December 31, 2025, there was $4,526 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 1.41 years. The total fair value of shares vested, including awards with deferred settlements, during the years ended December 31, 2025, 2024, and 2023, was $5,907, $31,257, and $35,204, respectively.

Performance-Based Restricted Stock Units

Relative Performance-Based Restricted Stock Units

The relative total shareholder return performance-based restricted stock units granted during the years ended December 31, 2025, 2024, and 2023 were valued relative to the stock price performance of a comparator group and had a weighted average grant date fair value based on assumptions incorporated in a Monte Carlo simulation as presented in the following table:

Year Ended December 31,
Relative performance-based restricted stock units202520242023
Weighted average grant date fair value$231.59 $531.08 $267.18 
Start price (1)
$216.98 $316.88 $151.35 
Valuation date stock price (2)
$193.40 $389.97 $176.44 
Expected volatility (3)
57.69 %64.21 %102.06 %
Risk-free interest rate (4)
4.29 %4.16 %3.82 %
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, 2024, 2023 and 2022, respectively, 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 value 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.

Relative performance-based restricted stock unit activity for the year ended December 31, 2025 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, 202433,378 $251.61 
Granted12,111 $231.59 
Vested (1)
(11,879)$97.33 
Forfeited(523)$297.20 
Non-vested shares outstanding at December 31, 202533,087 $298.95 
(1)     Excludes 10,244 net shares issued due to achievement of performance metrics above the 100% targeted performance level pursuant to the award agreement.

As of December 31, 2025, there was $3,052 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 1.65 years. The total fair value of shares vested during the years ended December 31, 2025, 2024, and 2023 was $2,303, $26,847, and $3,559, respectively, excluding net shares issued above the 100% targeted performance level.
Operational Performance-Based Restricted Stock Units
Operational performance-based restricted stock unit activity for the year ended December 31, 2025 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, 202450,054 $170.75 
Granted18,168 $196.42 
Vested (1)
(12,410)$60.37 
Forfeited/Canceled(6,193)$79.77 
Non-vested shares outstanding at December 31, 202549,619 $219.11 
(1)     Excludes 5,075 net shares issued due to achievement of performance metrics above the 100% targeted performance level pursuant to the award agreement.

As of December 31, 2025, there was $801 of unrecognized compensation cost related to non-vested operational performance-based restricted stock units, based on the probability of achievement as of December 31, 2025, which is expected to be recognized as expense over a weighted-average period of 1.20 years.The total fair value of shares vested during the years ended December 31, 2025, 2024, and 2023 was $2,406, $40,270, and $5,339, respectively, excluding net shares issued above the 100% targeted performance level.
Performance-Based Cash Incentive Awards
The performance-based cash incentive awards granted during the year ended December 31, 2022 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 based on assumptions incorporated in a Monte Carlo simulation as presented in the following table:
Performance-based cash incentive awardsYear Ended December 31, 2022
Weighted average grant date fair value61.97 %
Start price (1)
$53.29 
Valuation date stock price (2)
$61.09 
Expected volatility (3)
106.48 %
Risk-free interest rate (4)
1.26 %
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, 2021, 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.

Performance-based cash incentive award activity for the year ended December 31, 2025 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, 2024$990 186.23 %
Granted— — %
Vested(990)186.23 %
Forfeited— — %
Non-vested awards outstanding at December 31, 2025$— — %
v3.25.4
Related Party Transactions
12 Months Ended
Dec. 31, 2025
Related Party Transactions [Abstract]  
Related Party Transactions Related Party Transactions
There were no material related party transactions for the years ended December 31, 2025 and 2024.

As described in Note 10, the Company routinely provides capital contributions to DTA, its equity method investee. Refer to Notes 10 and 20 for further information.
v3.25.4
Commitments and Contingencies
12 Months Ended
Dec. 31, 2025
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 11 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 $103,035, $141,812, and $185,398 for the years ended December 31, 2025, 2024, and 2023, respectively.

Minimum royalty obligations under coal leases total $16,859, $16,163, $15,104, $13,745, $13,642, and $99,215 for 2026, 2027, 2028, 2029, 2030, and after 2030, respectively.

Other Commitments

As of December 31, 2025, the Company has obligations under certain coal purchase agreements that contain minimum quantities to be purchased in 2026 totaling an estimated $11,072. The Company also has outstanding unconditional purchase obligations for 2026, 2027, 2028, 2029, and 2030 totaling $117,517, $53,633, $14,246, 14,667, and 3,693 respectively, related to the purchase of equipment, as well as for rail freight and export terminal costs (including $39,618 in 2026 for DTA funding.)

Under the terms of its partnership related agreements with respect to its investment in DTA, the Company is required to fund its proportionate share of DTA’s ongoing operating and capital costs. In November 2023, the Company, together with DTA management announced that DTA needs additional capital investment to maximize functionality and minimize downtime due to mechanical issues. Beyond the Company’s share of routine operating costs, it expects to invest an average of approximately $21,000 per year for infrastructure and equipment upgrades at DTA over the next 5 years. In addition, to mitigate the risk of shipment delays during the upgrade period, in April 2024, the Company entered into a 3-year agreement which allows for the loading of 1,200 to 2,000 tons of coal annually at a third party terminal in Newport News, VA. The Company’s 2025 funding of DTA includes routine operating and capital costs and infrastructure and equipment upgrades.

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.

(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 LCs, 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 LCs to collateralize certain obligations and commitments.

As of December 31, 2025, the company had $41,254 LCs outstanding under the ABL Facility.
As of December 31, 2025, the Company had outstanding surety bonds with a total face amount of $170,014 to secure various obligations and commitments. To secure the Company’s reclamation-related obligations, the Company has $28,197 of collateral in the form of restricted cash and restricted investments supporting these obligations as of December 31, 2025.

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 the Company’s 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 LCs, 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 the 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 bonds.

Amounts included in restricted cash provide collateral to secure the following obligations:

December 31,
20252024
Workers’ compensation and black lung obligations$117,150 $113,144 
Reclamation-related obligations959 697 
Financial payments and other performance obligations8,802 8,742 
Total long-term restricted cash$126,911 $122,583 

Amounts included in restricted investments provide collateral to secure the following obligations:

December 31,
20252024
Workers’ compensation obligations$3,172 $3,119 
Reclamation-related obligations27,238 34,018 
Financial payments and other performance obligations3,946 5,994 
Total restricted investments (1)
$34,356 $43,131 
(1)     Classified as long-term trading securities as of December 31, 2025 and 2024.

Amounts included in deposits provide collateral to secure the following obligations:
December 31,
20252024
Workers’ compensation obligations$4,108 $4,108 
Other operating agreements 684 866 
Total deposits$4,792 $4,974 
Less current portion— (21)
Total deposits, net of current portion (1)
$4,792 $4,953 
(1)     Included within Other non-current assets on the Company’s Consolidated Balance Sheets.

DCMWC Reauthorization Process

In January 2025, the U.S. Department of Labor (“DOL”) published a final rule revising the requirements and procedures for authorizing operators to self-insure their liabilities under the Black Lung Benefits Act (the “2025 Final Rule”), and the Company anticipates it would require a substantial increase in the collateral required to secure self-insured federal black lung obligations. Under the 2025 Final Rule’s 100% minimum collateral requirement, if this requirement is not modified or stayed through legal action, the Company estimates it would be required to provide approximately $80,000 to $100,000 of collateral to secure certain of its black lung obligations. The 2025 Final Rule permits the Company to use combinations of letters of credit, surety bonds, and cash to meet the collateral requirement. The Company received a letter from the Division of Coal Mine
Workers’ Compensation (“DCMWC”) dated January 14, 2025, outlining the new procedures and application process for authorizing operators to self-insure under the new regulation. The letter outlined authorization form requirements and provided a 60-day period for the submission of the required documents. Subsequently, on February 20, 2025, the Company received a letter from the DCMWC stating that the 60-day deadline to provide information was no longer applicable and no information was required to be submitted at this time. DCMWC stated that additional guidance would be provided in due course after consultation with new DOL leadership. The Company continues to evaluate the potential impact of the 2025 Final Rule and awaits further communication from the DCMWC.

(d) Legal Proceedings

In December 2024, the state of New York adopted the Climate Change Superfund Act, purporting to impose significant, ongoing cash charges upon a variety of companies involved in the production and use of fossil fuels, including the Company (the “Act”). Other states have adopted or are contemplating adopting similar laws. The Company believes that the new law is unconstitutional under the U.S. Constitution. In February 2025, the Company, along with numerous U.S. states and other entities involved in the fossil fuel industry, filed a complaint against the attorney general of New York and other New York officials. The complaint was filed in the federal district court for the Northern District of New York and requests that the court (a) declare that the Act is preempted by federal statutes and otherwise violates the U.S. Constitution, (b) declare that the Act is unenforceable, and (c) enjoin the state of New York and its officials from taking any action to implement or enforce the Act. On May 1, 2025, the U.S. Department of Justice and the Environmental Protection Agency filed a similar complaint against the State of New York, Kathleen Hochul in her capacity as Governor, Letitia James in her capacity as New York Attorney General and Amanda Lefton in her capacity as Acting Commissioner of the New York Department of Environmental Conservation in the Southern District of New York, requesting that the court declare the Act unconstitutional and permanently enjoin its implementation or enforcement. Although the Company believes that the Act is very unlikely to be upheld, the outcome cannot be predicted with certainty. If the Act, or similar acts adopted in other U.S. states, were upheld, the Company’s liquidity would be materially, adversely affected.

In addition, the Company is party to other legal proceedings from time to time that occur in the ordinary course of business. 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, subsidence, 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 the 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.
v3.25.4
Concentration of Credit Risk and Major Customers
12 Months Ended
Dec. 31, 2025
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. The following table presents additional information on the Company’s total revenues and top customers:
Year Ended December 31,
 202520242023
Total coal revenues$2,122,605 $2,946,579 $3,456,630 
Total revenues$2,129,481 $2,957,285 $3,471,417 
Export coal revenues$1,557,086 $2,309,777 $2,539,068 
Top customer as % of total revenues 14 %16 %13 %
Top 10 customers as % of total revenues77 %75 %74 %
Number of customers exceeding 10% of total revenues
Number of customers exceeding 10% of total trade accounts receivable, net
Domestic coal revenue as % of total coal revenues 27 %22 %26 %
Export coal revenue as % of total coal revenues73 %78 %74 %
Countries with export coal revenue exceeding 10% of total revenuesIndiaIndia, BrazilIndia
Met coal as % of coal sales volume93 %93 %90 %
Thermal coal as % of coal sales volume%%10 %
v3.25.4
Segment Information
12 Months Ended
Dec. 31, 2025
Segment Reporting [Abstract]  
Segment Information Segment Information
The Company currently conducts its mining operations within the Central Appalachia (“CAPP”) coal basin located in the United States. The Company has one reportable operating segment: Met, which consists of six active mining complexes whose primary product is metallurgical quality coal that is extracted, processed, and marketed to domestic and international steel and coke producers. In addition to its primary product, thermal quality coal may also be produced as a by-product and marketed to domestic and international utilities and industrial customers. The segment’s equity method investment in DTA facilitates the export of coal to international customers. For 2023, the Company’s All Other category includes its former CAPP – Thermal operations, which consisted of mining complexes whose primary product was thermal coal. Segment operating results are regularly reviewed by the Company’s Chief Executive Officer, who is considered its Chief Operating Decision Maker (“CODM”). Beginning in 2024, following the cessation of mining within the Company’s former CAPP-Thermal operations, the Company’s CODM began to manage the Company on a consolidated basis. For 2023, income tax expense was allocated among segments by applying the Company’s consolidated annual effective income tax rate to segment earnings.
Met reportable segment results for the years ended December 31, 2025, 2024, and 2023 are as follows:

Year Ended December 31,
202520242023
Coal revenues$2,122,605 $2,946,579 $3,406,643 
Other revenues6,876 10,706 14,787 
Total revenues$2,129,481 $2,957,285 $3,421,430 
Non-GAAP Cost of coal sales$1,562,012 $1,918,427 $1,847,363 
Freight and handling costs333,691 503,306 438,783 
Idled and closed mine costs28,988 29,868 18,579 
Cost of coal sales (exclusive of items shown separately below)$1,924,691 $2,451,601 $2,304,725 
Depreciation, depletion and amortization$174,524 $167,331 $127,721 
Accretion on asset retirement obligations22,126 25,050 15,471 
Amortization of acquired intangibles5,427 6,700 8,523 
Selling, general and administrative expenses60,158 74,000 81,321 
Interest expense3,019 3,811 6,923 
Interest income(15,466)(18,208)(11,933)
Equity loss in affiliates24,867 20,302 18,263 
Other segment items (1)
17,594 15,948 3,284 
Income tax (benefit) expense(25,772)23,171 126,669 
Total other expenses$266,477 $318,105 $376,242 
Net (loss) income$(61,687)$187,579 $740,463 
(1)     Other segments items include Other operating loss (income), Loss on extinguishment of debt, and Miscellaneous expense, net.
No segment level asset information has been disclosed as the CODM does not review asset information by segment. Refer to the Company’s Consolidated Balance Sheets, Statements of Cash Flows, and Note 10 for information on its consolidated assets, capital expenditures, and equity method investments, respectively.

Reconciliations of reportable segment items to consolidated amounts for the year ended December 31, 2023 are as follows:

Year Ended December 31, 2023
MetAll OtherConsolidated
Total revenues$3,421,430 $49,987 $3,471,417 
Depreciation, depletion and amortization$127,721 $9,148 $136,869 
Accretion on asset retirement obligations$15,471 $10,029 $25,500 
Income tax expense (benefit)$126,669 $(3,166)$123,503 
Net income (loss)$740,463 $(18,507)$721,956 
v3.25.4
Insider Trading Arrangements
3 Months Ended
Dec. 31, 2025
Trading Arrangements, by Individual  
Rule 10b5-1 Arrangement Adopted false
Non-Rule 10b5-1 Arrangement Adopted false
Rule 10b5-1 Arrangement Terminated false
Non-Rule 10b5-1 Arrangement Terminated false
v3.25.4
Insider Trading Policies and Procedures
12 Months Ended
Dec. 31, 2025
Insider Trading Policies and Procedures [Line Items]  
Insider Trading Policies and Procedures Adopted true
v3.25.4
Cybersecurity Risk Management and Strategy Disclosure
12 Months Ended
Dec. 31, 2025
Cybersecurity Risk Management, Strategy, and Governance [Line Items]  
Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]
Risk Assessment and Management

We have become increasingly dependent upon digital technologies, including information systems, infrastructure and cloud applications and services, to operate our businesses, process and record financial and operating data, communicate with our employees and business partners, analyze seismic and drilling information, estimate quantities of met coal reserves, as well as other activities related to our businesses. We own and operate some of these systems and applications while others are owned and operated by third-party service providers.
We maintain a cybersecurity program employing many components and strategies to mitigate and remediate day-to-day cybersecurity threats and exposures. This program, along with a robust information technology internal controls framework, helps to ensure the confidentiality, integrity and availability of our information systems. The program includes elements for identifying, assessing and managing material risks from cybersecurity threats. Our incident response and change management policies and procedures were designed based on guidelines from the National Institute of Standards and Technology Cybersecurity Framework.

We take a risk-based approach to cybersecurity, which begins with the identification and evaluation of cybersecurity risks or threats that could affect our operations, finances, legal or regulatory compliance, or reputation. We employ continuous monitoring systems and other technologies and security controls to assist us with the identification of cybersecurity risks and threats. At least annually we conduct a third-party risk assessment to identify cybersecurity risks associated with third-party vendors and service providers. When cybersecurity risks are identified, we prioritize mitigation strategies based upon risks’ potential impact, likelihood, velocity and vulnerability, considering both quantitative and qualitative factors. These strategies include, among others, the application, adoption or modification of cybersecurity policies and procedures, implementation of administrative, technical and physical controls and employee training, education and awareness initiatives.

Our cybersecurity risk management includes continuous monitoring of networks and systems for potential signs of suspicious activity. Our Information Systems and Technology Department (the “IT Department”) monitors security alerts or indicators and initiates triage, verification and remediation actions when needed. We also provide mechanisms and training for employees to report to the IT Department any unusual or potentially malicious activity they observe for proper identification and analysis.

In the event of a significant cybersecurity incident, we establish an incident response team that works in conjunction with the IT Department to identify, contain, eradicate and, if necessary, recover from a cybersecurity incident. Through third parties we are also able to rapidly deploy forensic analysis, legal services, notification and call center services and credit and identity monitoring if required.

We track key performance indicators and cybersecurity metrics to evaluate the efficacy of our cybersecurity controls and practices. Further, our cybersecurity program is periodically reviewed by senior members of management and adjusted as needed in an effort to maintain the program’s agility and responsiveness as circumstances and technologies evolve, new cybersecurity threats emerge and regulations change.

In addition, we operate an enterprise risk management (“ERM”) program to identify, evaluate and manage risks. Cybersecurity risks are evaluated alongside other critical business risks under the ERM program to align cybersecurity efforts with our broader business goals and objectives. We believe that integrating cybersecurity risks into our ERM program fosters a proactive and holistic approach to cybersecurity, which helps safeguard our operations, financial condition and reputation in an ever-evolving threat landscape. Cybersecurity risks are further considered and evaluated as part of an annual risk assessment performed independently by our internal audit department.

Incident Response

We maintain an incident response policy and program focused upon detecting, managing, documenting and reporting incidents affecting our systems and data, including those specific to cybersecurity. In the event of a significant cybersecurity incident, we appoint a dedicated incident team, including a team leader, responsible for managing and coordinating incident response efforts. These efforts may include detecting, identifying, defending against, responding to and, if necessary, recovering from cybersecurity incidents. Incidents that meet certain thresholds are escalated to senior members of management, internal legal advisors, communication specialists and other key stakeholders for additional guidance and action.

Use of Third Parties

Cybersecurity Service Providers and Third-Party Consultants. At least annually we engage independent cybersecurity consultants, auditors and other third parties to assess and enhance our cybersecurity risk assessment and practices. These third parties conduct independent assessments, penetration testing and vulnerability assessments to identify weaknesses and recommend improvements. Additionally, we employ a number of third-party tools and technologies as part of our efforts to enhance cybersecurity functions and monitoring.

Oversight of Third-Party Service Providers. We use third-party service providers to support our operations and many of our technology initiatives, including third parties that house financial or sensitive information. Our technology acquisition
policy and our internal controls framework require us to obtain and review attestation reports regarding these third-party service providers and their sub-service processors or providers and their internal controls, complementary user entity controls and contractual obligations, including those specific to cybersecurity. We evaluate cybersecurity risks associated with our use of third-party service providers, which may include a review of a service provider’s cybersecurity posture or a recommendation of specific mitigation controls. We determine and prioritize service provider risk based on potential threat impact and likelihood and these risk determinations determine the level of due diligence and ongoing compliance monitoring required for each service provider.

Risks from Material Cybersecurity Threats

As of the date of this report, we have not identified any cybersecurity threats that have materially affected or are reasonably anticipated to have a material effect on the organization. Although we have not previously experienced cybersecurity incidents that are individually, or in the aggregate, material, we have experienced cyberattacks in the past, which we believe have thus far been deflected or mitigated by our preventative, detective and responsive measures. For additional discussion of our cybersecurity related risks, refer to “Item 1.A Risk Factors.”
Cybersecurity Risk Management Processes Integrated [Flag] true
Cybersecurity Risk Management Processes Integrated [Text Block]
We maintain a cybersecurity program employing many components and strategies to mitigate and remediate day-to-day cybersecurity threats and exposures. This program, along with a robust information technology internal controls framework, helps to ensure the confidentiality, integrity and availability of our information systems. The program includes elements for identifying, assessing and managing material risks from cybersecurity threats. Our incident response and change management policies and procedures were designed based on guidelines from the National Institute of Standards and Technology Cybersecurity Framework.

We take a risk-based approach to cybersecurity, which begins with the identification and evaluation of cybersecurity risks or threats that could affect our operations, finances, legal or regulatory compliance, or reputation. We employ continuous monitoring systems and other technologies and security controls to assist us with the identification of cybersecurity risks and threats. At least annually we conduct a third-party risk assessment to identify cybersecurity risks associated with third-party vendors and service providers. When cybersecurity risks are identified, we prioritize mitigation strategies based upon risks’ potential impact, likelihood, velocity and vulnerability, considering both quantitative and qualitative factors. These strategies include, among others, the application, adoption or modification of cybersecurity policies and procedures, implementation of administrative, technical and physical controls and employee training, education and awareness initiatives.

Our cybersecurity risk management includes continuous monitoring of networks and systems for potential signs of suspicious activity. Our Information Systems and Technology Department (the “IT Department”) monitors security alerts or indicators and initiates triage, verification and remediation actions when needed. We also provide mechanisms and training for employees to report to the IT Department any unusual or potentially malicious activity they observe for proper identification and analysis.

In the event of a significant cybersecurity incident, we establish an incident response team that works in conjunction with the IT Department to identify, contain, eradicate and, if necessary, recover from a cybersecurity incident. Through third parties we are also able to rapidly deploy forensic analysis, legal services, notification and call center services and credit and identity monitoring if required.

We track key performance indicators and cybersecurity metrics to evaluate the efficacy of our cybersecurity controls and practices. Further, our cybersecurity program is periodically reviewed by senior members of management and adjusted as needed in an effort to maintain the program’s agility and responsiveness as circumstances and technologies evolve, new cybersecurity threats emerge and regulations change.
In addition, we operate an enterprise risk management (“ERM”) program to identify, evaluate and manage risks. Cybersecurity risks are evaluated alongside other critical business risks under the ERM program to align cybersecurity efforts with our broader business goals and objectives. We believe that integrating cybersecurity risks into our ERM program fosters a proactive and holistic approach to cybersecurity, which helps safeguard our operations, financial condition and reputation in an ever-evolving threat landscape. Cybersecurity risks are further considered and evaluated as part of an annual risk assessment performed independently by our internal audit department.
Cybersecurity Risk Management Third Party Engaged [Flag] true
Cybersecurity Risk Third Party Oversight and Identification Processes [Flag] true
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag] false
Cybersecurity Risk Board of Directors Oversight [Text Block]
Board Oversight

The Board is responsible for overseeing management’s assessments of major risks facing us and for reviewing options to mitigate these risks. The Board’s oversight of cybersecurity risks occurs at both the Board level and through its Audit Committee.

The Board. The Chief Executive Officer, the Chief Operating Officer, the Chief Financial Officer, other members of senior management and other personnel and advisors, as requested by the Board, report on our financial, operating and commercial strategies, as well as major related risks, which may include cybersecurity risks, at regularly scheduled meetings of the Board. The Board may request follow-up data and presentations to address any specific concerns or recommendations.

The Audit Committee. The Audit Committee reviews with our management team, including our Senior Vice President – Information Systems and Technology, our cybersecurity frameworks, policies, technologies, programs, opportunities, strategies and risks. These presentations highlight any significant cybersecurity incidents, the cyber threat landscape, cybersecurity program enhancements, cybersecurity risks, related remediation and mitigation activities, security user awareness and reporting training program and any other relevant cybersecurity topics. In addition, members of our Legal Department advise the Audit Committee as needed regarding cybersecurity-related legal matters, including disclosure requirements. Management believes that these reports help to provide the Audit Committee with an informed understanding of our cybersecurity program, risks and strategies. The Audit Committee may request follow-up data and presentations to address any specific concerns or recommendations. In addition to this periodic reporting, significant cybersecurity risks or threats may also be escalated to the Audit Committee as needed based upon our cyber incident reporting process. The Audit Committee reports regularly to the entire Board and reviews with the Board any major issues that arise at the committee level, which may include cybersecurity risks.
Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block] The Board’s oversight of cybersecurity risks occurs at both the Board level and through its Audit Committee.
Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block]
The Board. The Chief Executive Officer, the Chief Operating Officer, the Chief Financial Officer, other members of senior management and other personnel and advisors, as requested by the Board, report on our financial, operating and commercial strategies, as well as major related risks, which may include cybersecurity risks, at regularly scheduled meetings of the Board. The Board may request follow-up data and presentations to address any specific concerns or recommendations.

The Audit Committee. The Audit Committee reviews with our management team, including our Senior Vice President – Information Systems and Technology, our cybersecurity frameworks, policies, technologies, programs, opportunities, strategies and risks. These presentations highlight any significant cybersecurity incidents, the cyber threat landscape, cybersecurity program enhancements, cybersecurity risks, related remediation and mitigation activities, security user awareness and reporting training program and any other relevant cybersecurity topics. In addition, members of our Legal Department advise the Audit Committee as needed regarding cybersecurity-related legal matters, including disclosure requirements. Management believes that these reports help to provide the Audit Committee with an informed understanding of our cybersecurity program, risks and strategies. The Audit Committee may request follow-up data and presentations to address any specific concerns or recommendations. In addition to this periodic reporting, significant cybersecurity risks or threats may also be escalated to the Audit Committee as needed based upon our cyber incident reporting process. The Audit Committee reports regularly to the entire Board and reviews with the Board any major issues that arise at the committee level, which may include cybersecurity risks.
Cybersecurity Risk Role of Management [Text Block]
Management’s Role

Our IT Department addresses current and emerging cybersecurity matters. This function is led by our Senior Vice President – Information Systems and Technology, who reports to our Chief Financial Officer. The IT Department’s security team, a cross-functional group composed of members who all have 7 to 27 years of professional and technical information technology experience, oversees the cybersecurity program to help ensure the confidentiality, integrity and availability of our systems and mitigate day-to-day threats and exposures. It is responsible for measuring and managing cybersecurity risk, including the prevention, detection, mitigation and remediation of cybersecurity incidents and also for implementing cybersecurity policies, programs, procedures and strategies. The security team reports significant cybersecurity incidents to senior management, internal legal advisors, communication specialists and other key stakeholders as required.
Cybersecurity Risk Management Positions or Committees Responsible [Flag] true
Cybersecurity Risk Management Positions or Committees Responsible [Text Block] Our IT Department addresses current and emerging cybersecurity matters. This function is led by our Senior Vice President – Information Systems and Technology, who reports to our Chief Financial Officer.
Cybersecurity Risk Management Expertise of Management Responsible [Text Block] The IT Department’s security team, a cross-functional group composed of members who all have 7 to 27 years of professional and technical information technology experience, oversees the cybersecurity program to help ensure the confidentiality, integrity and availability of our systems and mitigate day-to-day threats and exposures. It is responsible for measuring and managing cybersecurity risk, including the prevention, detection, mitigation and remediation of cybersecurity incidents and also for implementing cybersecurity policies, programs, procedures and strategies.
Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block]
Our IT Department addresses current and emerging cybersecurity matters. This function is led by our Senior Vice President – Information Systems and Technology, who reports to our Chief Financial Officer. The IT Department’s security team, a cross-functional group composed of members who all have 7 to 27 years of professional and technical information technology experience, oversees the cybersecurity program to help ensure the confidentiality, integrity and availability of our systems and mitigate day-to-day threats and exposures. It is responsible for measuring and managing cybersecurity risk, including the prevention, detection, mitigation and remediation of cybersecurity incidents and also for implementing cybersecurity policies, programs, procedures and strategies. The security team reports significant cybersecurity incidents to senior management, internal legal advisors, communication specialists and other key stakeholders as required.
Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag] true
v3.25.4
Summary of Significant Accounting Policies (Policies)
12 Months Ended
Dec. 31, 2025
Accounting Policies [Abstract]  
Basis of Presentation
Basis of Presentation

Together, the consolidated statements of operations, comprehensive (loss) income, balance sheets, cash flows and stockholders’ equity for the Company are referred to as the “Consolidated Financial Statements.” The Consolidated Financial Statements are also referenced across periods as “Consolidated Statements of Operations,” “Consolidated Statements of Comprehensive (Loss) Income,” “Consolidated Balance Sheets,” “Consolidated Statements of Cash Flows,” and “Consolidated Statements of Stockholders’ Equity.”

The Consolidated Financial Statements include all wholly owned subsidiaries’ results of operations for the years ended December 31, 2025, 2024, and 2023. 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”).
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 payable; income taxes refundable and receivable; reserves for contingencies and litigation; and fair value of financial instruments. 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 Cash
Amounts included in restricted cash represent cash and cash equivalents 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.
Investments
Investments

Short-term investments, with maturities of twelve months or less, consist of U.S government securities. Restricted investments consist of U.S. government 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.
All investments are classified as trading securities as of December 31, 2025 and 2024. Trading securities are recorded initially at cost and are adjusted to fair value at each reporting period with unrealized gains and losses recorded in current period earnings or loss.
Deposits
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.
Trade Accounts Receivable and Allowance for Credit Losses
Trade Accounts Receivable and Allowance for Credit Losses
Trade accounts receivable are recorded at their invoiced amounts and do not bear interest. The Company markets its coal primarily to international and domestic 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 (“LCs”), 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.
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.
Advanced Mining Royalties
Advanced Mining Royalties
Lease rights to coal reserves are often acquired in exchange for royalty payments. Advanced mining royalties are advanced payments made to lessors under terms of mineral lease agreements that are recoupable against future production royalties. These advanced payments are deferred and charged to operations as the coal reserves are mined. The Company regularly reviews recoverability of advanced mining royalties and establishes or adjusts the allowance for advanced mining royalties as necessary using the specific identification method. Advanced royalty balances are generally charged off against the allowance when they are no longer recoupable. Advanced mining royalties are included within Other non-current assets on the Company’s Consolidated Balance Sheets.
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 operating loss (income) in the Company’s Consolidated Statements of Operations.
Owned and Leased Mineral Rights
Owned and Leased Mineral Rights

Owned and leased mineral rights, net of accumulated depletion and amortization, for the years ended December 31, 2025 and 2024 were $416,944 and $443,467, respectively, and are reported in assets in the Company’s Consolidated Balance Sheets. These amounts include $37,005 and $41,552 of asset retirement obligation assets, net of accumulated amortization, associated with active mining operations for the years ended December 31, 2025 and 2024, respectively.

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 Consolidated Statements of Operations and was $22,258, $28,075, and $23,944 for the years ended December 31, 2025, 2024, and 2023 respectively.
Depletion expense for the years ended December 31, 2025, 2024, and 2023 includes a credit of ($6,137), an expense of $961, and a credit of ($34), respectively, related to revisions to asset retirement obligations.
Leases
Leases
In accordance with Accounting Standards Codification (“ASC”) 842 Lease Accounting (“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 Intangibles
The Company has recognized assets for acquired mine permits which were valued based on the replacement cost and lost profits method as of the Merger date. The balances of such assets are included within Other acquired intangibles, net of accumulated amortization, on the Company’s Consolidated Balance Sheets. The acquired mine permits are amortized over the estimated life of the associated mine. Amortization expense is included in Amortization of acquired intangibles in the Consolidated Statements of Operations.
Goodwill
Goodwill

Goodwill represents the excess of the purchase price over the fair value of the net identifiable tangible and intangible assets of acquired companies. Goodwill is not amortized; instead, it is tested for impairment annually as of October 31 of each year or more frequently if indicators of impairment exist. Goodwill is included in the Consolidated Balance Sheets as Other Non-Current Assets.
The Company assesses goodwill for impairment on a qualitative basis. If the Company determines that more likely than not the fair value of a reporting unit containing goodwill exceeds its carrying amount, no further impairment testing is required. If the qualitative assessment indicates that an impairment potentially exists, then the Company quantitatively tests goodwill for impairment by comparing the fair value of the reporting unit to its carrying amount. If the fair value of the reporting unit is lower than its carrying amount, its goodwill is written down by the lesser of the amount by which the reporting units carrying amount exceeded its fair value or its carrying amount of goodwill.
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.
As of June 30, 2025, due to recent declines in metallurgical coal spot pricing, the Marfork, Power Mountain, Elk Run and Kepler mining complexes were tested for impairment. Estimated future undiscounted cash flows were projected to exceed each complex’s respective carrying value and no impairment charges were required.
Asset Retirement Obligations
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. On at least an annual basis, the Company reviews its estimated future cash flows for its asset retirement obligations.
Income Taxes
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.
Deferred Financing Costs
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
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, 2025, 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, 2025 and 2024, the workers’ compensation liability was net of a discount of $20,968 and $21,587, respectively, related to fair value adjustments associated with acquisition accounting. Refer to Note 17 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, 2025, 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 17 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 17 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.
Net (Loss) Income per Share
Net (Loss) Income per Share
 Basic net (loss) income per share is computed by dividing net (loss) income by the weighted-average number of outstanding common shares for the period. Diluted 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 earnings per share is computed by increasing the weighted-average number of outstanding common shares computed in basic earnings per share to include the additional common shares that would be outstanding after issuance and adjusting net (loss) income 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.
Stock-Based Compensation
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.
Warrants
Warrants
On July 26, 2016 (the “Initial Issue Date”), the Company issued warrants, which were classified as equity instruments, and were exercisable for cash or on a cashless basis at any time from the Initial Issue Date until July 26, 2023, and no fractional shares were issued upon warrant exercises. The exercise price and the warrant share number were adjusted in respect of certain dilutive events with respect to common stock. At 5:00 pm Eastern time on July 26, 2023 the Company’s Series A Warrants expired pursuant to their terms.
Equity Method Investments
Equity Method Investments
Investments and membership interests in joint ventures are accounted for under the equity method of accounting if the Company has the ability to exercise significant influence, but not control, over the entity. Under the equity method of accounting, the Company’s proportionate share of the entity’s comprehensive income or loss each reporting period is reflected in Equity loss in affiliates in the Consolidated Statements of Operations. Equity method investments are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the investment may not be recoverable. The carrying values of the Company’s equity method investments are included within Other non-current assets on the Company’s Consolidated Balance Sheets.
Recent Adopted Accounting Guidance and Recent Accounting Guidance Issued Not Yet Effective
Recently Adopted Accounting Guidance

Income Tax Disclosures: In December 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (“ASU 2023-09”). This update requires public business entities to disclose in their income tax rate reconciliation table additional categories of information about federal, state, and foreign income taxes and to provide additional details about the reconciling items in categories meeting a quantitative threshold. The guidance will also require entities to disclose income taxes paid, net of refunds, disaggregated by federal, state, and foreign taxes for annual periods and to disaggregate the information by jurisdiction based
on a quantitative threshold. The additional disclosures are required to be provided on a prospective basis with the option to provide retrospectively. The amendments are effective for fiscal years beginning after December 15, 2024. The Company adopted ASU 2023-09 retrospectively during the fourth quarter of 2025 and prior period disclosures have been recast to conform to the current year presentation. Refer to Note 16 for the additional required income tax disclosures upon adoption of this ASU.

Recent Accounting Guidance Issued Not Yet Effective

Expense Disaggregation Disclosures: In November 2024, the FASB issued ASU 2024-03, Income Statement – Reporting Comprehensive Income – Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses (“ASU 2024-03”). This update requires public entities to disaggregate income statement expense line items and to disclose in tabular format within the notes to the financial statements certain categories of costs (e.g. purchases of inventory, employee compensation, deprecation, intangible asset amortization, depletion etc.) to the extent line items contain such costs. In addition, entities will be required to define and disclose selling expenses. The additional disclosures may be provided prospectively or retrospectively. The amendments are effective for annual reporting periods beginning after December 15, 2026, and interim periods within annual reporting periods beginning after December 15, 2027. Early adoption is permitted. The Company will provide the additional required disclosures upon adoption.
v3.25.4
Revenue (Tables)
12 Months Ended
Dec. 31, 2025
Revenue from Contract with Customer [Abstract]  
Schedule of 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,
202520242023
Export met coal revenues$1,500,265 $2,237,571 $2,412,960 
Export thermal coal revenues56,821 72,206 126,108 
Total export coal revenues$1,557,086 $2,309,777 $2,539,068 
Domestic met coal revenues$530,195 $608,971 $865,667 
Domestic thermal coal revenues35,324 27,831 51,895 
Total domestic coal revenues$565,519 $636,802 $917,562 
Total met coal revenues$2,030,460 $2,846,542 $3,278,627 
Total thermal coal revenues92,145 100,037 178,003 
Total coal revenues$2,122,605 $2,946,579 $3,456,630 
Schedule of 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, 2025.
20262027202820292030Total
Estimated coal revenues (1)
$83,560 $12,300 $— $— $— $95,860 
(1)     Amounts include only estimated coal revenues associated with contracts with customers with fixed pricing with original expected duration of more than one year. The Company has elected not to disclose the aggregate amount of the transaction price allocated to the performance obligations that are unsatisfied (or partially unsatisfied) as of the end of the reporting period for performance obligations with either of the following conditions: 1) the remaining performance obligation is part of a contract that has an original expected duration of one year or less; or 2) the remaining performance obligation has variable consideration that is allocated entirely to a wholly unsatisfied performance obligation.
v3.25.4
Accumulated Other Comprehensive Loss (Tables)
12 Months Ended
Dec. 31, 2025
Equity [Abstract]  
Schedule of Accumulated Other Comprehensive Loss
The following tables summarize the changes to accumulated other comprehensive loss during the years ended December 31, 2025, 2024, and 2023:
Balance January 1, 2025Other comprehensive loss before reclassificationsAmounts reclassified from accumulated other comprehensive lossBalance December 31, 2025
Employee benefit costs$(50,082)$(14,766)$4,415 $(60,433)
Balance January 1, 2024
Other comprehensive loss before reclassificationsAmounts reclassified from accumulated other comprehensive loss
Balance December 31, 2024
Employee benefit costs$(40,587)$(12,963)$3,468 $(50,082)
Balance January 1, 2023
Other comprehensive loss before reclassificationsAmounts reclassified from accumulated other comprehensive loss
Balance December 31, 2023
Employee benefit costs$(12,162)$(26,617)$(1,808)$(40,587)
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, 2025, 2024, and 2023:
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,
202520242023
Employee benefit costs:
Amortization of actuarial loss (gain) (1)
$5,645 $4,431 $(2,324)
Miscellaneous expense, net
Settlement (1)
— 26 — 
Miscellaneous expense, net
Total before income tax$5,645 $4,457 $(2,324)
Income tax (expense) benefit(1,230)(989)516 Income tax benefit (expense)
Total, net of income tax$4,415 $3,468 $(1,808)
(1)     These accumulated other comprehensive loss components are included in the computation of net periodic benefit costs (credits) for certain employee benefit plans. Refer to Note 17.
v3.25.4
Net (Loss) Income Per Share (Tables)
12 Months Ended
Dec. 31, 2025
Earnings Per Share [Abstract]  
Schedule of Net (Loss) income Per Common Share
The following table presents the net (loss) income per common share for the years ended December 31, 2025, 2024, and 2023:

Year Ended December 31,
202520242023
Basic
Net (loss) income$(61,687)$187,579 $721,956 
Weighted average common shares outstanding - basic12,996,148 13,013,469 14,106,466 
Net (loss) income per common share - basic$(4.75)$14.41 $51.18 
Diluted
Weighted average common shares outstanding - basic12,996,148 13,013,469 14,106,466 
Diluted effect of warrants— — 81,352 
Diluted effect of stock options— — 1,400 
Diluted effect of other stock-based instruments— 121,337 453,638 
Weighted average common shares outstanding - diluted12,996,148 13,134,806 14,642,856 
Net (loss) income per common share - diluted$(4.75)$14.28 $49.30 
v3.25.4
Inventories, net (Tables)
12 Months Ended
Dec. 31, 2025
Inventory Disclosure [Abstract]  
Schedule of Inventory
Inventories, net consisted of the following: 
December 31,
 20252024
Raw coal$41,665 $39,689 
Saleable coal81,919 65,129 
Materials, supplies and other, net 69,416 64,451 
Total inventories, net$193,000 $169,269 
v3.25.4
Property, Plant, and Equipment, net (Tables)
12 Months Ended
Dec. 31, 2025
Property, Plant and Equipment [Abstract]  
Schedule of Property, Plant, and Equipment, Net
Property, plant, and equipment, net, consisted of the following: 
December 31,
 20252024
Plant and mining equipment$1,050,261 $1,024,467 
Mine development241,154 199,419 
Land33,089 33,180 
Office equipment, software and other5,861 5,603 
Construction in progress65,602 39,462 
Total property, equipment and mine development costs$1,395,967 $1,302,131 
Less accumulated depreciation and amortization(774,101)(667,260)
Total property, plant, and equipment, net$621,866 $634,871 
v3.25.4
Other Non-Current Assets (Tables)
12 Months Ended
Dec. 31, 2025
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,
20252024
Advanced mining royalties$8,975 $9,482 
Long-term deposits4,792 4,953 
Equity method investments53,850 41,072 
Workers’ compensation receivables30,365 34,075 
Goodwill11,124 11,124 
Other10,596 10,886 
Total other non-current assets$119,702 $111,592 
v3.25.4
Leases (Tables)
12 Months Ended
Dec. 31, 2025
Leases [Abstract]  
Schedule of Right-of-use Assets and Lease Liabilities
As of December 31, 2025 and 2024, the Company had the following right-of-use assets and lease liabilities within the Company’s Consolidated Balance Sheets:
December 31, 2025December 31, 2024
AssetsBalance Sheet Classification
Financing lease assetsProperty, plant, and equipment, net$10,953 $4,434 
Operating lease right-of-use assetsOther non-current assets5,337 3,564 
Total lease assets$16,290 $7,998 
LiabilitiesBalance Sheet Classification
Financing lease liabilities - currentCurrent portion of long-term debt$2,108 $1,332 
Operating lease liabilities - currentAccrued expenses and other current liabilities690 597 
Financing lease liabilities - long-termLong-term debt7,452 2,666 
Operating lease liabilities - long-termOther non-current liabilities4,647 2,967 
Total lease liabilities$14,897 $7,562 
Schedule of Lease Costs and Other Information
Total lease costs and other lease information for the years ended December 31, 2025, 2024, and 2023 included the following:
Year Ended December 31,
202520242023
Lease cost (1)
Financing lease cost:
     Amortization of leased assets$1,577 $1,513 $1,444 
     Interest on lease liabilities418 571 651 
Operating lease cost995 1,012 1,127 
Short-term lease cost1,316 1,181 1,315 
     Total lease cost$4,306 $4,277 $4,537 
(1)     The Company had no variable lease costs or sublease income for the years ended December 31, 2025, 2024, and 2023.
Year Ended December 31,
202520242023
Other information
Cash paid for amounts included in the measurement of lease liabilities$5,261 $4,042 $4,571 
     Operating cash flows from financing leases$418 $571 $651 
     Operating cash flows from operating leases$2,310 $2,193 $2,443 
     Financing cash flows from financing leases$2,533 $1,278 $1,477 
Right-of-use assets obtained in exchange for new financing lease liabilities$7,949 $— $1,891 
Right-of-use assets obtained in exchange for new operating lease liabilities$2,316 $103 $206 
Lease Term and Discount Rate
Weighted-average remaining lease term in years - financing leases5.004.605.10
Weighted-average remaining lease term in years - operating leases6.505.506.30
Weighted-average discount rate - financing leases8.1 %12.2 %12.3 %
Weighted-average discount rate - operating leases9.6 %11.5 %11.4 %
Schedule of 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, 2025:
Financing LeasesOperating Leases
Lease cost
2026$2,734 $1,234 
20272,243 1,214 
20281,956 1,195 
20291,956 1,179 
20301,956 1,132 
Thereafter814 1,238 
Total future minimum lease payments$11,659 $7,192 
Imputed interest(2,099)(1,855)
Present value of future minimum lease payments$9,560 $5,337 
Schedule of 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, 2025:
Financing LeasesOperating Leases
Lease cost
2026$2,734 $1,234 
20272,243 1,214 
20281,956 1,195 
20291,956 1,179 
20301,956 1,132 
Thereafter814 1,238 
Total future minimum lease payments$11,659 $7,192 
Imputed interest(2,099)(1,855)
Present value of future minimum lease payments$9,560 $5,337 
v3.25.4
Accrued Expenses and Other Current Liabilities (Tables)
12 Months Ended
Dec. 31, 2025
Payables and Accruals [Abstract]  
Schedule of Accrued Expenses and Other Current Liabilities
Accrued expenses and other current liabilities consisted of the following: 
December 31,
 20252024
Wages and benefits$46,687 $48,642 
Workers’ compensation 8,880 9,444 
Black lung 12,329 11,209 
Taxes other than income taxes26,315 27,995 
Asset retirement obligations22,632 29,938 
Freight accrual12,018 16,144 
Other 6,917 8,188 
Total accrued expenses and other current liabilities$135,778 $151,560 
v3.25.4
Long-Term Debt (Tables)
12 Months Ended
Dec. 31, 2025
Debt Disclosure [Abstract]  
Schedule of Long-term Debt Instruments
Long-term debt consisted of the following: 
December 31,
 20252024
Notes payable and other$3,856 $1,786 
Financing leases9,560 3,998 
Total long-term debt $13,416 $5,784 
Less current portion(3,575)(2,916)
Long-term debt, net of current portion$9,841 $2,868 
Schedule of Maturities of Long-term Debt
Future maturities of long-term debt as of December 31, 2025 are as follows: 
2026$3,575 
20273,055 
20282,600 
20291,667 
20301,795 
After 2030724 
Total long-term debt$13,416 
v3.25.4
Asset Retirement Obligations (Tables)
12 Months Ended
Dec. 31, 2025
Asset Retirement Obligation Disclosure [Abstract]  
Schedule of Changes in Asset Retirement Obligations
The following table summarizes the changes in asset retirement obligations for the years ended December 31, 2025 and 2024:
Total asset retirement obligations at December 31, 2023$205,424 
Accretion for the period 25,050 
Sites added during the period5,381 
Revisions in estimated cash flows (1)
12,414 
Expenditures for the period(28,526)
Total asset retirement obligations at December 31, 2024$219,743 
Accretion for the period22,126 
Sites added during the period 475 
Revisions in estimated cash flows 61 
Expenditures for the period(15,028)
Total asset retirement obligations at December 31, 2025$227,377 
Less current portion (2)
(22,632)
Long-term portion$204,745 
(1)    The revisions in estimated cash flows for the year ended December 31, 2024 resulted primarily from a decrease in the discount rate and changes in mine plans.
(2)    Included within Accrued expenses and other current liabilities on the Company’s Consolidated Balance Sheets. Refer to Note 12.
v3.25.4
Fair Value of Financial Instruments and Fair Value Measurements (Tables)
12 Months Ended
Dec. 31, 2025
Fair Value Disclosures [Abstract]  
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, 2025 and 2024. 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, 2025
Total Fair ValueQuoted Prices in Active Markets (Level 1)Significant Other Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Trading securities (1)
$83,938 $— $83,938 $— 
(1)     Includes $49,582 classified as Short-term investments and $34,356 classified as Long-term restricted investments on the Company’s Consolidated Balance Sheets.

 December 31, 2024
Total Fair ValueQuoted Prices in Active Markets (Level 1)Significant Other Observable Inputs (Level 2)Significant Unobservable Inputs (Level 3)
Trading securities (1)
$43,131 $— $43,131 $— 
(1)     Classified as Long-term restricted investments on the Company’s Consolidated Balance Sheets.
v3.25.4
Income Taxes (Tables)
12 Months Ended
Dec. 31, 2025
Income Tax Disclosure [Abstract]  
Schedule of Components of Income Tax (Benefit) Expense
Significant components of income tax (benefit) expense were as follows:
Year Ended December 31,
202520242023
Current tax (benefit) expense:
Federal$(1,977)$17,219 $80,254 
State(55)389 3,527 
Total current$(2,032)$17,608 $83,781 
Deferred tax (benefit) expense:
Federal$(22,301)$3,868 $35,824 
State(1,439)1,695 3,898 
Total deferred $(23,740)$5,563 $39,722 
Total income tax (benefit) expense:
Federal$(24,278)$21,087 $116,078 
State(1,494)2,084 7,425 
Total$(25,772)$23,171 $123,503 
Schedule of Effective Income Tax Rate Reconciliation
A reconciliation of statutory federal income tax expense on income to the actual income tax expense is as follows:
Year Ended December 31, 2025Year Ended December 31, 2024Year Ended December 31, 2023
AmountPercentAmountPercentAmountPercent
U.S. federal statutory tax rate$(18,366)21.0 %$44,258 21.0 %$177,547 21.0 %
State and local income taxes, net of federal income tax effect (1)
(1,181)1.4 %1,647 0.8 %5,866 0.7 %
Effect of cross-border tax laws
Foreign-derived intangible income deduction— — %(2,718)(1.3)%(24,291)(2.9)%
Change in valuation allowances(43,361)49.6 %(341)(0.2)%(3,045)(0.4)%
Nontaxable or nondeductible items
Percentage depletion allowance(9,586)11.0 %(20,245)(9.6)%(36,685)(4.3)%
Non-deductible compensation2,691 (3.1)%28,320 13.4 %9,934 1.2 %
Stock-based compensation(1,124)1.3 %(28,710)(13.6)%(6,968)(0.8)%
Other, net866 (1.0)%907 0.4 %653 0.1 %
Other adjustments
Capital loss expiration43,261 (49.5)%— — %— — %
Provision-to-return adjustment1,045 (1.2)%188 0.1 %683 0.1 %
Other, net(17)— %(135)— %(191)(0.1)%
Effective tax rate$(25,772)29.5 %$23,171 11.0 %$123,503 14.6 %
(1)    State taxes in Illinois, Virginia, and West Virginia made up the majority (greater than 50 percent) of the tax effect in this category.
Schedule of Income Taxes Paid
The amounts of cash taxes paid (net of refunds received) by the Company are as follows:
Year Ended December 31,
202520242023
US federal$— $11,000 $75,700 
US state and local
Kentucky(174)(1,308)(8)
Tennessee125 351 45 
Virginia2,225 (1,756)3,037 
Other(58)92 417 
Total$2,118 $8,379 $79,191 
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,
20252024
Deferred tax assets:
  Asset retirement obligations$49,773 $47,561 
  Reserves and accruals not currently deductible9,107 9,021 
  Workers’ compensation and black lung obligations41,659 38,538 
Pension obligations17,336 18,246 
Net operating loss carryforwards43,323 31,810 
Capital loss carryforwards— 45,072 
  Other 8,046 10,878 
     Gross deferred tax assets169,244 201,126 
Less valuation allowance(3,159)(48,734)
     Deferred tax assets$166,085 $152,392 
Deferred tax liabilities:
Property, plant and mineral reserves$(161,917)$(174,031)
  Acquired intangibles(6,250)(7,371)
  Prepaid expenses(3,648)(3,900)
  Other (1,616)(1,060)
     Total deferred tax liabilities(173,431)(186,362)
     Net deferred tax liabilities$(7,346)$(33,970)
Schedule of Valuation Allowance
Changes in the valuation allowance were as follows:
Year Ended December 31,
202520242023
Valuation allowance beginning of period$48,734 $48,143 $53,801 
(Decrease) increase in valuation allowance recorded to income tax expense (45,575)591 (5,658)
Valuation allowance end of period$3,159 $48,734 $48,143 
v3.25.4
Employee Benefit Plans (Tables)
12 Months Ended
Dec. 31, 2025
Compensation Related Costs [Abstract]  
Schedule of Changes in Accumulated Benefits Obligations, Fair Value of Plan Assets and Funded Status of Plan
The following tables set forth the Pension Plan’s accumulated benefit obligation, fair value of plan assets and funded status for the years ended December 31, 2025 and 2024.
Year Ended December 31,
20252024
Change in benefit obligations:
Accumulated benefit obligation at beginning of period:$451,976 $478,366 
Interest cost 23,254 23,672 
Actuarial loss (gain)13,487 (17,715)
Benefits paid(31,312)(32,347)
Accumulated benefit obligation at end of period$457,405 $451,976 
Change in fair value of plan assets:
Fair value of plan assets at beginning of period$351,379 $376,458 
Actual return on plan assets33,055 (5,052)
Employer contributions16,966 12,320 
Benefits paid(31,312)(32,347)
Fair value of plan assets at end of period$370,088 $351,379 
Funded status$(87,317)$(100,597)
Accrued benefit cost at end of period (1)
$(87,317)$(100,597)
(1)     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, 2025 and 2024:
Year Ended December 31,
20252024
Change in benefit obligation:
Accumulated benefit obligation at beginning of period$116,956 $109,871 
Service cost2,141 2,404 
Interest cost5,852 5,229 
Actuarial loss18,865 9,086 
Benefits paid(10,435)(9,634)
Accumulated benefit obligation at end of period$133,379 $116,956 
Change in fair value of plan assets:
Fair value of plan assets at beginning of period$2,683 $2,613 
Actual return on plan assets87 70 
Benefits paid(10,435)(9,634)
Employer contributions10,435 9,634 
Fair value of plan assets at end of period (1)
2,770 2,683 
Funded status$(130,609)$(114,273)
Accrued benefit cost at end of period$(130,609)$(114,273)
(1)     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.
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, 2025 and 2024:
December 31,
20252024
Net actuarial loss$31,053 $32,545 
Gross amounts related to the black lung benefit obligations recognized in accumulated other comprehensive loss consisted of the following as of December 31, 2025 and 2024: 
December 31,
20252024
Net actuarial loss$33,341 $18,814 
Schedule of Net Periodic Benefit Cost
The following table details the components of net periodic benefit cost:
Year Ended December 31,
202520242023
Interest cost$23,254 $23,672 $23,973 
Expected return on plan assets(19,673)(20,913)(21,996)
Amortization of net actuarial loss1,597 1,764 730 
Net periodic benefit cost$5,178 $4,523 $2,707 
The following table details the components of the net periodic benefit cost for the black lung benefit obligations:
Year Ended December 31,
202520242023
Service cost$2,141 $2,404 $2,051 
Interest cost5,852 5,229 4,660 
Expected return on plan assets(54)(52)(50)
Amortization of net actuarial loss (gain)4,305 2,884 (2,833)
Net periodic benefit cost$12,244 $10,465 $3,828 
Schedule of Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive (Loss) Income
Other changes in plan assets and benefit obligation recognized in other comprehensive (loss) income are as follows:
Year Ended December 31,
202520242023
Actuarial loss (1)
$105 $8,250 $14,106 
Amortization of net actuarial loss(1,597)(1,764)(730)
Total recognized in other comprehensive (loss) income$(1,492)$6,486 $13,376 
(1) For the year ended December 31, 2024, the actuarial loss was primarily attributable to lower than expected return on plan assets and an annual census data actuarial revaluation of pension obligations, partially offset by an increase in the weighted-average discount rate actuarial assumption used in determining the benefit obligation.
Other changes in the black lung plan assets and benefit obligations recognized in other comprehensive income (loss) are as follows:
Year Ended December 31,
202520242023
Actuarial loss (1)
$18,832 $9,068 $19,995 
Amortization of net actuarial (loss) gain(4,305)(2,884)2,833 
Total recognized in other comprehensive income$14,527 $6,184 $22,828 
(1)     For the year ended December 31, 2025, the actuarial loss was primarily attributable to changes in demographic assumptions and a decrease in the weighted-average discount rate actuarial assumption used in determining the benefit obligations. For the year ended December 31, 2024, the actuarial loss was primarily attributable to an increase in new claimants and claims and changes in demographic assumptions, partially offset by an increase in the weighted-average discount rate actuarial assumption used in determining the benefit obligations.
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,
20252024
Projected benefit obligation$457,405 $451,976 
Accumulated benefit obligation$457,405 $451,976 
Fair value of plan assets$370,088 $351,379 
Schedule of Assumptions Used
The weighted-average actuarial assumption used in determining the benefit obligation as of December 31, 2025 and 2024 was as follows: 
December 31,
20252024
Discount rate5.44 %5.65 %

The weighted-average actuarial assumptions used to determine net periodic benefit cost (credit) for the years ended December 31, 2025, 2024, and 2023 were as follows: 
Year Ended December 31,
202520242023
Discount rate for benefit obligation5.65 %5.12 %5.42 %
Discount rate for interest cost5.33 %4.99 %5.27 %
 Expected long-term rate of return on plan assets (1)
5.70 %5.70 %6.20 %
(1)     During the three months ended June 30, 2024, the Company updated the 2024 expected long-term rate of return on plan assets from 6.20% to 5.70% based on a weighted basis of the beginning and more recently assumed rate as the pension plan’s target allocation was updated to 50% equity securities and 50% fixed income funds in the interim period.
The weighted-average assumptions related to black lung obligations used to determine the benefit obligation as of December 31, 2025 and 2024 were as follows: 
December 31,
20252024
Discount rate5.46 %5.66 %
Federal black lung income benefit trend rate2.50 %2.50 %
Federal black lung medical benefit trend rate5.00 %5.00 %

The weighted-average assumptions related to black lung benefit obligations used to determine net periodic benefit cost were as follows:
Year Ended December 31,
202520242023
Discount rate for benefit obligation5.66 %5.13 %5.42 %
Discount rate for service cost5.88 %5.31 %5.58 %
Discount rate for interest cost5.27 %4.98 %5.23 %
Federal black lung income benefit trend rate2.50 %2.50 %2.50 %
Federal black lung medical benefit trend rate5.00 %5.00 %5.00 %
Expected return on plan assets2.00 %2.00 %2.00 %
Schedule of Allocation of Plan Assets The target allocation for 2026 and the actual asset allocation as reported at December 31, 2025 are as follows:
Target Allocation Percentages 2026Percentage of Plan Assets 2025
Equity securities50.0 %50.0 %
Fixed income funds50.0 %44.0 %
Other— %6.0 %
Total100.0 %100.0 %
Schedule of Estimated Cash Payments
The following represents expected future pension benefit payments for the next ten years:
2026$31,937 
202731,822 
202831,526 
202931,236 
203030,964 
2031-2035152,532 
$310,017 
Estimated future cash payments related to black lung benefit obligations for the next 10 years ending after December 31, 2025 are as follows: 
Year ending December 31:
2026$12,329 
202712,200 
202811,960 
202911,769 
203011,703 
2031-2035
33,695 
$93,656 
Schedule of Changes in Fair Value of Plan Assets
The fair values of the Company’s Pension Plan’s assets as of December 31, 2025, by asset category are as follows:
Asset Category
Total
Level 1Level 2Level 3
Assets Measured at NAV (1)
Equity securities:
ETF funds
$97,401 $97,401 $— $— $— 
Mutual funds87,179 87,179 — — — 
Fixed income funds:
Corporate bonds
92,076 — 92,076 — — 
U.S. government securities68,270 — 68,270 — — 
Commingled short-term fund (2)
1,196 — 1,196 — — 
Private equity funds404 — — — 404 
Other types of investments:
Guaranteed insurance contract12,488 — — 12,488 — 
Total$359,014 $184,580 $161,542 $12,488 $404 
Cash & cash equivalents (3)
8,931 
Receivable (4)
2,143 
Total plan assets$370,088 
(1)    In accordance with ASU 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.
(2)    This fund contains cash and highly liquid short-term investments in a collective investment fund.
(3)    Represents cash on deposit that has FDIC insurance, which approximates fair value.
(4)    Receivable for investments sold at December 31, 2025, which approximates fair value.
The fair values of the Company’s Pension Plan’s assets as of December 31, 2024, by asset category are as follows:
Asset Category
Total
Level 1Level 2Level 3
Assets Measured at NAV (1)
Equity securities:
Multi-asset fund
$170,829 $— $170,829 $— $— 
Fixed income funds:
Bond fund
165,100 — 165,100 — — 
Commingled short-term fund (2)
1,269 — 1,269 — — 
Private equity funds
448 — — — 448 
Other types of investments:
Guaranteed insurance contract12,488 — — 12,488 — 
Total$350,134 $— $337,198 $12,488 $448 
Receivable (3)
1,245 
Total plan assets$351,379 
(1)    In accordance with ASU 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.
(2)    This fund contains cash and highly liquid short-term investments in a collective investment fund.
(3)    Receivable for investments sold at December 31, 2024, which approximates fair value.

Changes in Level 3 plan assets for the period ended December 31, 2024 were as follows:
Level 3
Guaranteed Insurance Contract
Beginning balance, December 31, 2023$12,230 
Actual return on plan assets:
Relating to assets still held at the reporting date524 
Purchases, sales and settlements(266)
Ending balance, December 31, 2024$12,488 
Schedule of Workers' Compensation
The table below presents workers’ compensation amounts recognized in the Consolidated Balance Sheets:
December 31,
20252024
Current liabilities$8,880 $9,444 
Long-term liabilities72,685 79,897 
Total liabilities$81,565 $89,341 
Less expected insurance receivable (1)
(31,947)(35,891)
Workers’ compensation obligations, net of expected insurance receivables$49,618 $53,450 
(1)     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,
20252024
Current liabilities$12,329 $11,209 
Long-term liabilities118,280 103,064 
Total liabilities$130,609 $114,273 
v3.25.4
Stock-Based Compensation Awards (Tables)
12 Months Ended
Dec. 31, 2025
Share-Based Payment Arrangement [Abstract]  
Schedule of Restricted Stock Units Activity
Time-based restricted stock unit activity for the year ended December 31, 2025 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, 202443,330 $252.62 
Granted50,335 $185.77 
Vested (1)
(31,276)$175.00 
Forfeited(1,025)$249.49 
Non-vested shares outstanding at December 31, 202561,364 $237.40 
(1)     Includes 8,071 shares with deferred settlement pursuant to the award agreements.
Schedule of Valuation Assumptions
The relative total shareholder return performance-based restricted stock units granted during the years ended December 31, 2025, 2024, and 2023 were valued relative to the stock price performance of a comparator group and had a weighted average grant date fair value based on assumptions incorporated in a Monte Carlo simulation as presented in the following table:

Year Ended December 31,
Relative performance-based restricted stock units202520242023
Weighted average grant date fair value$231.59 $531.08 $267.18 
Start price (1)
$216.98 $316.88 $151.35 
Valuation date stock price (2)
$193.40 $389.97 $176.44 
Expected volatility (3)
57.69 %64.21 %102.06 %
Risk-free interest rate (4)
4.29 %4.16 %3.82 %
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, 2024, 2023 and 2022, respectively, 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 value 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 performance-based cash incentive awards granted during the year ended December 31, 2022 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 based on assumptions incorporated in a Monte Carlo simulation as presented in the following table:
Performance-based cash incentive awardsYear Ended December 31, 2022
Weighted average grant date fair value61.97 %
Start price (1)
$53.29 
Valuation date stock price (2)
$61.09 
Expected volatility (3)
106.48 %
Risk-free interest rate (4)
1.26 %
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, 2021, 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.
Schedule of Performance Shares Activity
Relative performance-based restricted stock unit activity for the year ended December 31, 2025 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, 202433,378 $251.61 
Granted12,111 $231.59 
Vested (1)
(11,879)$97.33 
Forfeited(523)$297.20 
Non-vested shares outstanding at December 31, 202533,087 $298.95 
(1)     Excludes 10,244 net shares issued due to achievement of performance metrics above the 100% targeted performance level pursuant to the award agreement.
Operational performance-based restricted stock unit activity for the year ended December 31, 2025 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, 202450,054 $170.75 
Granted18,168 $196.42 
Vested (1)
(12,410)$60.37 
Forfeited/Canceled(6,193)$79.77 
Non-vested shares outstanding at December 31, 202549,619 $219.11 
(1)     Excludes 5,075 net shares issued due to achievement of performance metrics above the 100% targeted performance level pursuant to the award agreement.
Performance-based cash incentive award activity for the year ended December 31, 2025 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, 2024$990 186.23 %
Granted— — %
Vested(990)186.23 %
Forfeited— — %
Non-vested awards outstanding at December 31, 2025$— — %
v3.25.4
Commitment and Contingencies (Tables)
12 Months Ended
Dec. 31, 2025
Commitments and Contingencies Disclosure [Abstract]  
Schedule of Restrictions on Cash and Cash Equivalents
Amounts included in restricted cash provide collateral to secure the following obligations:

December 31,
20252024
Workers’ compensation and black lung obligations$117,150 $113,144 
Reclamation-related obligations959 697 
Financial payments and other performance obligations8,802 8,742 
Total long-term restricted cash$126,911 $122,583 
Schedule of Prepaid Expenses and Other Current Assets
Amounts included in restricted investments provide collateral to secure the following obligations:

December 31,
20252024
Workers’ compensation obligations$3,172 $3,119 
Reclamation-related obligations27,238 34,018 
Financial payments and other performance obligations3,946 5,994 
Total restricted investments (1)
$34,356 $43,131 
(1)     Classified as long-term trading securities as of December 31, 2025 and 2024.

Amounts included in deposits provide collateral to secure the following obligations:
December 31,
20252024
Workers’ compensation obligations$4,108 $4,108 
Other operating agreements 684 866 
Total deposits$4,792 $4,974 
Less current portion— (21)
Total deposits, net of current portion (1)
$4,792 $4,953 
(1)     Included within Other non-current assets on the Company’s Consolidated Balance Sheets.
v3.25.4
Concentration of Credit Risk and Major Customers (Tables)
12 Months Ended
Dec. 31, 2025
Risks and Uncertainties [Abstract]  
Schedule of Concentration of Credit Risk and Major Customers The following table presents additional information on the Company’s total revenues and top customers:
Year Ended December 31,
 202520242023
Total coal revenues$2,122,605 $2,946,579 $3,456,630 
Total revenues$2,129,481 $2,957,285 $3,471,417 
Export coal revenues$1,557,086 $2,309,777 $2,539,068 
Top customer as % of total revenues 14 %16 %13 %
Top 10 customers as % of total revenues77 %75 %74 %
Number of customers exceeding 10% of total revenues
Number of customers exceeding 10% of total trade accounts receivable, net
Domestic coal revenue as % of total coal revenues 27 %22 %26 %
Export coal revenue as % of total coal revenues73 %78 %74 %
Countries with export coal revenue exceeding 10% of total revenuesIndiaIndia, BrazilIndia
Met coal as % of coal sales volume93 %93 %90 %
Thermal coal as % of coal sales volume%%10 %
v3.25.4
Segment Information (Tables)
12 Months Ended
Dec. 31, 2025
Segment Reporting [Abstract]  
Schedule of Segment Operating Results and Capital Expenditures
Met reportable segment results for the years ended December 31, 2025, 2024, and 2023 are as follows:

Year Ended December 31,
202520242023
Coal revenues$2,122,605 $2,946,579 $3,406,643 
Other revenues6,876 10,706 14,787 
Total revenues$2,129,481 $2,957,285 $3,421,430 
Non-GAAP Cost of coal sales$1,562,012 $1,918,427 $1,847,363 
Freight and handling costs333,691 503,306 438,783 
Idled and closed mine costs28,988 29,868 18,579 
Cost of coal sales (exclusive of items shown separately below)$1,924,691 $2,451,601 $2,304,725 
Depreciation, depletion and amortization$174,524 $167,331 $127,721 
Accretion on asset retirement obligations22,126 25,050 15,471 
Amortization of acquired intangibles5,427 6,700 8,523 
Selling, general and administrative expenses60,158 74,000 81,321 
Interest expense3,019 3,811 6,923 
Interest income(15,466)(18,208)(11,933)
Equity loss in affiliates24,867 20,302 18,263 
Other segment items (1)
17,594 15,948 3,284 
Income tax (benefit) expense(25,772)23,171 126,669 
Total other expenses$266,477 $318,105 $376,242 
Net (loss) income$(61,687)$187,579 $740,463 
(1)     Other segments items include Other operating loss (income), Loss on extinguishment of debt, and Miscellaneous expense, net.
Schedule of Reconciliation of Reportable Segment Items
Reconciliations of reportable segment items to consolidated amounts for the year ended December 31, 2023 are as follows:

Year Ended December 31, 2023
MetAll OtherConsolidated
Total revenues$3,421,430 $49,987 $3,471,417 
Depreciation, depletion and amortization$127,721 $9,148 $136,869 
Accretion on asset retirement obligations$15,471 $10,029 $25,500 
Income tax expense (benefit)$126,669 $(3,166)$123,503 
Net income (loss)$740,463 $(18,507)$721,956 
v3.25.4
Summary of Significant Accounting Policies - Property, Plant, and Equipment, Net (Details) - Mining equipment, buildings and other fixed assets
Dec. 31, 2025
Minimum  
Property, Plant and Equipment [Line Items]  
Property, plant and equipment, useful lives 1 year
Maximum  
Property, Plant and Equipment [Line Items]  
Property, plant and equipment, useful lives 25 years
v3.25.4
Summary of Significant Accounting Policies - Owned and Leased Mineral Rights (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Property, Plant and Equipment [Line Items]      
Owned and leased mineral rights $ 416,944 $ 443,467  
Asset retirement obligation assets 37,005 41,552  
Depletion 22,258 28,075 $ 23,944
Revisions to asset retirement obligations 61 12,414  
Mining Properties and Mineral Rights      
Property, Plant and Equipment [Line Items]      
Revisions to asset retirement obligations $ (6,137) $ 961 $ (34)
v3.25.4
Summary of Significant Accounting Policies - Acquired Intangibles (Details)
$ in Thousands
Dec. 31, 2025
USD ($)
Accounting Policies [Abstract]  
Future amortization expense, 2026 $ 4,913
Future amortization expense, 2027 4,837
Future amortization expense, 2028 4,837
Future amortization expense, 2029 4,799
Future amortization expense, 2030 1,342
Future amortization expense, after 2030 $ 13,724
v3.25.4
Summary of Significant Accounting Policies - Workers' Compensation (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Workers' Compensation Insurance    
Business Combination [Line Items]    
Short-duration contracts, discounted liabilities, amount $ 20,968 $ 21,587
v3.25.4
Revenue - Narrative (Details)
12 Months Ended
Dec. 31, 2025
Domestic  
Disaggregation of Revenue [Line Items]  
Contract term 1 year
v3.25.4
Revenue - Disaggregation of Revenue by Segment (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Disaggregation of Revenue [Line Items]      
Revenues $ 2,122,605 $ 2,946,579 $ 3,456,630
Coal revenues      
Disaggregation of Revenue [Line Items]      
Revenues 2,122,605 2,946,579 3,456,630
Coal revenues | Export      
Disaggregation of Revenue [Line Items]      
Revenues 1,557,086 2,309,777 2,539,068
Coal revenues | Domestic      
Disaggregation of Revenue [Line Items]      
Revenues 565,519 636,802 917,562
Coal, Met      
Disaggregation of Revenue [Line Items]      
Revenues 2,030,460 2,846,542 3,278,627
Coal, Met | Export      
Disaggregation of Revenue [Line Items]      
Revenues 1,500,265 2,237,571 2,412,960
Coal, Met | Domestic      
Disaggregation of Revenue [Line Items]      
Revenues 530,195 608,971 865,667
Thermal coal      
Disaggregation of Revenue [Line Items]      
Revenues 92,145 100,037 178,003
Thermal coal | Export      
Disaggregation of Revenue [Line Items]      
Revenues 56,821 72,206 126,108
Thermal coal | Domestic      
Disaggregation of Revenue [Line Items]      
Revenues $ 35,324 $ 27,831 $ 51,895
v3.25.4
Revenue - Performance Obligations (Details)
$ in Thousands
Dec. 31, 2025
USD ($)
Disaggregation of Revenue [Line Items]  
Estimated coal revenues $ 95,860
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01  
Disaggregation of Revenue [Line Items]  
Estimated coal revenues $ 83,560
Estimated coal revenues, period 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01  
Disaggregation of Revenue [Line Items]  
Estimated coal revenues $ 12,300
Estimated coal revenues, period 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01  
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]: 2029-01-01  
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]: 2030-01-01  
Disaggregation of Revenue [Line Items]  
Estimated coal revenues $ 0
Estimated coal revenues, period 1 year
v3.25.4
Accumulated Other Comprehensive Loss - Changes to Accumulated Other Comprehensive Loss (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
AOCI Attributable to Parent, Net of Tax [Roll Forward]      
Beginning balance $ 1,649,497 $ 1,573,928 $ 1,429,755
Ending balance 1,545,495 1,649,497 1,573,928
Employee benefit costs      
AOCI Attributable to Parent, Net of Tax [Roll Forward]      
Beginning balance (50,082) (40,587) (12,162)
Other comprehensive loss before reclassifications (14,766) (12,963) (26,617)
Amounts reclassified from accumulated other comprehensive loss 4,415 3,468 (1,808)
Ending balance $ (60,433) $ (50,082) $ (40,587)
v3.25.4
Accumulated Other Comprehensive Loss - Schedule of Amounts Reclassified (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Employee benefit costs:      
Miscellaneous expense, net $ (13,673) $ (11,199) $ (1,620)
Total before income tax (87,459) 210,750 845,459
Income tax benefit (expense) 25,772 (23,171) (123,503)
Net (loss) income (61,687) 187,579 721,956
Reclassification out of Accumulated Other Comprehensive Income | Employee benefit costs      
Employee benefit costs:      
Total before income tax 5,645 4,457 (2,324)
Income tax benefit (expense) (1,230) (989) 516
Net (loss) income 4,415 3,468 (1,808)
Reclassification out of Accumulated Other Comprehensive Income | Amortization of actuarial (gain) loss      
Employee benefit costs:      
Miscellaneous expense, net 5,645 4,431 (2,324)
Reclassification out of Accumulated Other Comprehensive Income | Settlement      
Employee benefit costs:      
Miscellaneous expense, net $ 0 $ 26 $ 0
v3.25.4
Net (Loss) Income Per Share - Narrative (Details) - shares
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Earnings Per Share [Abstract]      
Antidilutive securities excluded from computation of earnings per share (in shares) 0 159 1,240
Weighted average number of shares, impact of securities excluded from shares due to the company incurring net loss for the period (in shares) 36,761    
v3.25.4
Net (Loss) Income Per Share - Schedule of Net (Loss) Income Per Common Share (Details) - USD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Basic      
Net (loss) income $ (61,687) $ 187,579 $ 721,956
Weighted average common shares outstanding - basic (in shares) 12,996,148 13,013,469 14,106,466
Net (loss) income per common share - basic (in dollars per share) $ (4.75) $ 14.41 $ 51.18
Diluted      
Weighted average common shares outstanding - basic (in shares) 12,996,148 13,013,469 14,106,466
Diluted effect of warrants (in shares) 0 0 81,352
Weighted average common shares outstanding - diluted (in shares) 12,996,148 13,134,806 14,642,856
Net (loss) income per common share - diluted (in dollars per share) $ (4.75) $ 14.28 $ 49.30
Stock options      
Diluted      
Diluted effect of share-based payment awards (in shares) 0 0 1,400
Stock-based instruments      
Diluted      
Diluted effect of share-based payment awards (in shares) 0 121,337 453,638
v3.25.4
Inventories, net (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Inventory Disclosure [Abstract]    
Raw coal $ 41,665 $ 39,689
Saleable coal 81,919 65,129
Materials, supplies and other, net 69,416 64,451
Total inventories, net $ 193,000 $ 169,269
v3.25.4
Capital Stock - Share Repurchase Program (Details) - USD ($)
46 Months Ended
Dec. 31, 2025
Mar. 04, 2022
Equity [Abstract]    
Authorized share repurchases   $ 1,500,000,000
Number of shares repurchased 6,878,449  
Total share repurchase price $ 1,138,916,000  
Value of shares repurchased 1,138,709,000  
Shares repurchased, fees 207,000  
Accrued stock repurchase excise tax $ 327,000  
v3.25.4
Capital Stock - Warrants (Details) - USD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
Dec. 31, 2023
Jun. 15, 2023
Mar. 15, 2023
Dec. 15, 2022
Jul. 26, 2016
Equity [Abstract]          
Number of warrants outstanding (in shares) 0       810,811
Exercise price of warrants (in dollars per share)   $ 44.820 $ 44.972 $ 45.086  
Number of securities called by each warrant (in shares)       1.20  
Shares issued upon exercise of warrants (in shares) 169,028        
Shares withheld upon exercise of warrants (in shares) 20,139        
Amount reclassified as treasury stock $ 2,368        
v3.25.4
Property, Plant, and Equipment, net - Schedule of Property, Plant, and Equipment, Net (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Property, Plant and Equipment [Line Items]    
Total property, equipment and mine development costs $ 1,395,967 $ 1,302,131
Less accumulated depreciation and amortization (774,101) (667,260)
Total property, plant, and equipment, net 621,866 634,871
Plant and mining equipment    
Property, Plant and Equipment [Line Items]    
Total property, equipment and mine development costs 1,050,261 1,024,467
Mine development    
Property, Plant and Equipment [Line Items]    
Total property, equipment and mine development costs 241,154 199,419
Land    
Property, Plant and Equipment [Line Items]    
Total property, equipment and mine development costs 33,089 33,180
Office equipment, software and other    
Property, Plant and Equipment [Line Items]    
Total property, equipment and mine development costs 5,861 5,603
Construction in progress    
Property, Plant and Equipment [Line Items]    
Total property, equipment and mine development costs $ 65,602 $ 39,462
v3.25.4
Property, Plant, and Equipment, net - Narrative (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Property, Plant and Equipment [Line Items]      
Depreciation, depletion and amortization associated with property, plant and equipment $ 152,266 $ 139,256 $ 112,925
Revisions to asset retirement obligations 61 12,414  
Equipment purchase commitments      
Property, Plant and Equipment [Line Items]      
Unconditional purchase obligation, 2024 9,655    
Depreciation expense      
Property, Plant and Equipment [Line Items]      
Revisions to asset retirement obligations 3,092 (3,747) $ 7,343
Plant and mining equipment      
Property, Plant and Equipment [Line Items]      
Financing leases included in plant and mining equipment 15,780 10,963  
Financing leases, accumulated depreciation $ 4,827 $ 6,529  
v3.25.4
Other Non-Current Assets (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]    
Advanced mining royalties $ 8,975 $ 9,482
Long-term deposits 4,792 4,953
Equity method investments 53,850 41,072
Workers’ compensation receivables 30,365 34,075
Goodwill 11,124 11,124
Other 10,596 10,886
Total other non-current assets $ 119,702 $ 111,592
v3.25.4
Equity Method Investments - Narrative (Details)
Dec. 31, 2025
DTA  
Schedule of Equity Method Investments [Line Items]  
Ownership percentage 65.00%
v3.25.4
Leases - Right-of-use Assets and Lease Liabilities (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Assets    
Financing lease assets $ 10,953 $ 4,434
Operating lease right-of-use assets 5,337 3,564
Total lease assets $ 16,290 $ 7,998
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] Property, plant, and equipment, net of accumulated depreciation and amortization of $774,101 and $667,260 as of December 31, 2025 and 2024, respectively Property, plant, and equipment, net of accumulated depreciation and amortization of $774,101 and $667,260 as of December 31, 2025 and 2024, 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 $ 2,108 $ 1,332
Operating lease liabilities - current 690 597
Financing lease liabilities - long-term 7,452 2,666
Operating lease liabilities - long-term 4,647 2,967
Total lease liabilities $ 14,897 $ 7,562
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
v3.25.4
Leases - Lease Costs and Other Information (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Financing lease cost:      
Amortization of leased assets $ 1,577 $ 1,513 $ 1,444
Interest on lease liabilities 418 571 651
Operating lease cost 995 1,012 1,127
Short-term lease cost 1,316 1,181 1,315
Total lease cost 4,306 4,277 4,537
Variable lease income 0 0 0
Sublease income 0 0 0
Other information      
Cash paid for amounts included in the measurement of lease liabilities 5,261 4,042 4,571
Operating cash flows from financing leases 418 571 651
Operating cash flows from operating leases 2,310 2,193 2,443
Financing cash flows from financing leases 2,533 1,278 1,477
Right-of-use assets obtained in exchange for new financing lease liabilities 7,949 0 1,891
Right-of-use assets obtained in exchange for new operating lease liabilities $ 2,316 $ 103 $ 206
Lease Term and Discount Rate      
Weighted-average remaining lease term in years - financing leases 5 years 4 years 7 months 6 days 5 years 1 month 6 days
Weighted-average remaining lease term in years - operating leases 6 years 6 months 5 years 6 months 6 years 3 months 18 days
Weighted-average discount rate - financing leases 8.10% 12.20% 12.30%
Weighted-average discount rate - operating leases 9.60% 11.50% 11.40%
v3.25.4
Leases - Maturities of Lease Liabilities (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Financing Leases    
2026 $ 2,734  
2027 2,243  
2028 1,956  
2029 1,956  
2030 1,956  
Thereafter 814  
Total future minimum lease payments 11,659  
Imputed interest (2,099)  
Present value of future minimum lease payments 9,560 $ 3,998
Operating Leases    
2026 1,234  
2027 1,214  
2028 1,195  
2029 1,179  
2030 1,132  
Thereafter 1,238  
Total future minimum lease payments 7,192  
Imputed interest (1,855)  
Present value of future minimum lease payments $ 5,337  
v3.25.4
Accrued Expenses and Other Current Liabilities (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Payables and Accruals [Abstract]    
Wages and benefits $ 46,687 $ 48,642
Workers’ compensation 8,880 9,444
Black lung 12,329 11,209
Taxes other than income taxes 26,315 27,995
Asset retirement obligations 22,632 29,938
Freight accrual 12,018 16,144
Other 6,917 8,188
Accrued expenses and other current liabilities $ 135,778 $ 151,560
v3.25.4
Long-Term Debt - Schedule of Long-term Debt (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Debt Disclosure [Abstract]    
Notes payable and other $ 3,856 $ 1,786
Financing leases 9,560 3,998
Total long-term debt 13,416 5,784
Less current portion (3,575) (2,916)
Long-term debt, net of current portion $ 9,841 $ 2,868
v3.25.4
Long-Term Debt - ABL Agreement (Details) - USD ($)
12 Months Ended
May 06, 2025
Oct. 27, 2023
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Debt Instrument [Line Items]          
Loss on extinguishment of debt     $ 0 $ 0 $ 2,753,000
Second Amended and Restated Asset-Based Revolving Credit Agreement          
Debt Instrument [Line Items]          
Loss on extinguishment of debt   $ 2,753,000      
ABL Facility          
Debt Instrument [Line Items]          
SOFR adjustment rate (as a percent) 0.10%        
Amount outstanding on line of credit     0 0  
Letters of credit outstanding     41,254,000 $ 42,149,000  
ABL Facility | SOFR | Variable Rate Component One          
Debt Instrument [Line Items]          
Variable interest rate (as a percent) 2.25%        
ABL Facility | SOFR | Variable Rate Component Two          
Debt Instrument [Line Items]          
Variable interest rate (as a percent) 2.50%        
ABL Facility | SOFR | Variable Rate Component Three          
Debt Instrument [Line Items]          
Variable interest rate (as a percent) 2.75%        
ABL Facility | Base Rate | Variable Rate Component One          
Debt Instrument [Line Items]          
Variable interest rate (as a percent) 1.25%        
ABL Facility | Base Rate | Variable Rate Component Two          
Debt Instrument [Line Items]          
Variable interest rate (as a percent) 1.50%        
ABL Facility | Base Rate | Variable Rate Component Three          
Debt Instrument [Line Items]          
Variable interest rate (as a percent) 1.75%        
ABL Facility | Revolving Credit Facility          
Debt Instrument [Line Items]          
Aggregate amount $ 225,000,000 $ 155,000,000      
Additional borrowing capacity $ 75,000,000        
Commitment fee on unused capacity (as a percent) 0.375%        
Minimum cash level threshold $ 100,000,000   $ 100,000,000    
Compliance, minimum liquidity 75,000,000        
ABL Facility | Letter of Credit          
Debt Instrument [Line Items]          
Additional borrowing capacity $ 25,000,000        
Fronting fee (as a percent) 0.0025        
ABL Facility | Letter of Credit | Commitment Fee, Component One          
Debt Instrument [Line Items]          
Commitment fee (as a percent) 2.25%        
ABL Facility | Letter of Credit | Commitment Fee, Component Two          
Debt Instrument [Line Items]          
Commitment fee (as a percent) 2.50%        
ABL Facility | Letter of Credit | Commitment Fee, Component Three          
Debt Instrument [Line Items]          
Commitment fee (as a percent) 2.75%        
v3.25.4
Long-Term Debt - Schedule of Maturities of Long-term Debt (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Debt Disclosure [Abstract]    
2026 $ 3,575  
2027 3,055  
2028 2,600  
2029 1,667  
2030 1,795  
After 2030 724  
Total long-term debt $ 13,416 $ 5,784
v3.25.4
Asset Retirement Obligations (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]      
Total asset retirement obligations at beginning of period $ 219,743 $ 205,424  
Accretion for the period 22,126 25,050 $ 25,500
Sites added during the period 475 5,381  
Revisions in estimated cash flows 61 12,414  
Expenditures for the period (15,028) (28,526)  
Total assets retirement obligations at end of period 227,377 219,743 $ 205,424
Less current portion (22,632) (29,938)  
Long-term portion $ 204,745 $ 189,805  
v3.25.4
Fair Value of Financial Instruments and Fair Value Measurements - Schedule of Fair Value on Recurring Basis (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]    
Trading securities $ 83,938 $ 43,131
Short-term investments 49,582 0
Long-term restricted investments 34,356 43,131
Level 1    
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]    
Trading securities 0 0
Significant Other Observable Inputs (Level 2)    
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]    
Trading securities 83,938 43,131
Level 3    
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]    
Trading securities $ 0 $ 0
v3.25.4
Income Taxes - Components of Income Tax Expense (Benefit) (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Current tax (benefit) expense:      
Federal $ (1,977) $ 17,219 $ 80,254
State (55) 389 3,527
Total current (2,032) 17,608 83,781
Deferred tax (benefit) expense:      
Federal (22,301) 3,868 35,824
State (1,439) 1,695 3,898
Total deferred (23,740) 5,563 39,722
Total income tax (benefit) expense:      
Federal (24,278) 21,087 116,078
State (1,494) 2,084 7,425
Total $ (25,772) $ 23,171 $ 123,503
v3.25.4
Income Taxes - Effective Tax Rate Reconciliation (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Amount      
U.S. federal statutory tax rate $ (18,366) $ 44,258 $ 177,547
State and local income taxes, net of federal income tax effect (1,181) 1,647 5,866
Foreign-derived intangible income deduction 0 (2,718) (24,291)
Change in valuation allowances (43,361) (341) (3,045)
Percentage depletion allowance (9,586) (20,245) (36,685)
Non-deductible compensation 2,691 28,320 9,934
Stock-based compensation (1,124) (28,710) (6,968)
Other, net 866 907 653
Capital loss expiration 43,261 0 0
Provision-to-return adjustment 1,045 188 683
Other, net (17) (135) (191)
Total $ (25,772) $ 23,171 $ 123,503
Percent      
U.S. federal statutory tax rate (as a percent) 21.00% 21.00% 21.00%
State and local income taxes, net of federal income tax effect (as a percent) 1.40% 0.80% 0.70%
Foreign-derived intangible income deduction (as a percent) 0.00% (1.30%) (2.90%)
Change in valuation allowances (as a percent) 49.60% (0.20%) (0.40%)
Percentage depletion allowance (as a percent) 11.00% (9.60%) (4.30%)
Non-deductible compensation (as a percent) (3.10%) 13.40% 1.20%
Stock-based compensation (as a percent) 1.30% (13.60%) (0.80%)
Other, net (as a percent) (1.00%) 0.40% 0.10%
Capital loss expiration (as a percent) (49.50%) 0.00% 0.00%
Provision-to-return adjustment (1.20%) 0.10% 0.10%
Other, net (as a percent) 0.00% 0.00% (0.10%)
Effective tax rate (as a percent) 29.50% 11.00% 14.60%
v3.25.4
Income Taxes - Income Tax Paid (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Effective Income Tax Rate Reconciliation [Line Items]      
US federal $ 0 $ 11,000 $ 75,700
Total 2,118 8,379 79,191
Kentucky      
Effective Income Tax Rate Reconciliation [Line Items]      
US state and local (174) (1,308) (8)
Tennessee      
Effective Income Tax Rate Reconciliation [Line Items]      
US state and local 125 351 45
Virginia      
Effective Income Tax Rate Reconciliation [Line Items]      
US state and local 2,225 (1,756) 3,037
Other      
Effective Income Tax Rate Reconciliation [Line Items]      
US state and local $ (58) $ 92 $ 417
v3.25.4
Income Taxes - Deferred Income Taxes (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Deferred tax assets:        
Asset retirement obligations $ 49,773 $ 47,561    
Reserves and accruals not currently deductible 9,107 9,021    
Workers’ compensation and black lung obligations 41,659 38,538    
Pension obligations 17,336 18,246    
Net operating loss carryforwards 43,323 31,810    
Capital loss carryforwards 0 45,072    
Other 8,046 10,878    
Gross deferred tax assets 169,244 201,126    
Less valuation allowance (3,159) (48,734) $ (48,143) $ (53,801)
Deferred tax assets 166,085 152,392    
Deferred tax liabilities:        
Property, plant and mineral reserves (161,917) (174,031)    
Acquired intangibles (6,250) (7,371)    
Prepaid expenses (3,648) (3,900)    
Other (1,616) (1,060)    
Total deferred tax liabilities (173,431) (186,362)    
Net deferred tax liabilities $ (7,346) $ (33,970)    
v3.25.4
Income Taxes - Valuation Allowance (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Valuation Allowance, Deferred Tax Asset, Increase (Decrease) [Roll Forward]      
Valuation allowance beginning of period $ 48,734 $ 48,143 $ 53,801
(Decrease) increase in valuation allowance recorded to income tax expense (45,575) 591 (5,658)
Valuation allowance end of period $ 3,159 $ 48,734 $ 48,143
v3.25.4
Income Taxes - Narrative (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Tax Credit Carryforward [Line Items]      
Deferred tax assets on operating loss carryforwards $ 33,755    
Liability for uncertain tax positions 0 $ 0 $ 0
Interest and penalties related to uncertain tax positions 0 $ 0  
IRS      
Tax Credit Carryforward [Line Items]      
Operating loss carryforwards, not subject to limitations 53,000    
IRS | IRS Section 283 Limitation One      
Tax Credit Carryforward [Line Items]      
Operating loss carryforwards 11,000    
Operating loss carryforwards, subject to limitation 1,000    
IRS | IRS Section 382 Limitation Two      
Tax Credit Carryforward [Line Items]      
Operating loss carryforwards 97,000    
Operating loss carryforwards, subject to limitation 17,500    
Operating loss carryforwards, not subject to limitations $ 53,000    
v3.25.4
Employee Benefit Plans - Narrative (Details)
$ in Thousands
3 Months Ended 12 Months Ended
Nov. 09, 2018
plan
Dec. 31, 2025
USD ($)
Jun. 30, 2024
Mar. 31, 2024
Dec. 31, 2026
USD ($)
Dec. 31, 2025
USD ($)
Dec. 31, 2024
USD ($)
Dec. 31, 2023
USD ($)
plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Number of qualified plans | plan               1
Contributions to defined contribution and profit sharing plans           $ 6,578 $ 6,425 $ 16,435
Annual salaries (as a percent)   2.00%            
Self-insured medical expense           $ 106,551 $ 102,805 $ 86,745
Pension Plan                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Expected return on plan assets (as a percent)     5.70% 6.20%   5.70% 5.70% 6.20%
Employer contributions           $ 16,966 $ 12,320  
Benefit obligation   $ 87,317       $ 87,317 $ 100,597  
Pension Plan | Equity securities                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Target allocation (as a percent)   50.00%       50.00%    
Pension Plan | Fixed income funds                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Target allocation (as a percent)   50.00%       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)         5.70%      
Target allocation (as a percent)         100.00%      
Expected contributions in next fiscal year         $ 23,108      
Pension Plan | Forecast | Equity securities                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Target allocation (as a percent)         50.00%      
Pension Plan | Forecast | Fixed income funds                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Target allocation (as a percent)         50.00%      
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% 2.00%
Employer contributions           $ 10,435 $ 9,634  
High-deductible insurance premium expense for worker's compensation and black lung claims           8,113 9,461 $ 10,676
Workers' compensation (credit) expense for high-deductible insurance plans           4,385 (1,758) $ (271)
Benefit obligation   $ 130,609       130,609 114,273  
Black Lung | Current liabilities                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Benefit obligation   12,329       12,329 11,209  
Life Insurance Benefits                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Benefit obligation   8,259       8,259 8,222  
Life Insurance Benefits | Current liabilities                
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]                
Benefit obligation   $ 610       $ 610 $ 600  
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 | 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%       6.00%    
Alpha Companies | Pension 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%       4.00%    
v3.25.4
Employee Benefit Plans - Changes in Accumulated Benefits Obligations, Fair Value of Plan Assets and Funded Status of Plan (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Pension Plan      
Change in benefit obligation:      
Accumulated benefit obligation at beginning of period $ 451,976 $ 478,366  
Interest cost 23,254 23,672 $ 23,973
Actuarial loss (gain) 13,487 (17,715)  
Benefits paid (31,312) (32,347)  
Accumulated benefit obligation at end of period 457,405 451,976 478,366
Change in fair value of plan assets:      
Beginning balance 351,379 376,458  
Actual return on plan assets 33,055 (5,052)  
Employer contributions 16,966 12,320  
Benefits paid (31,312) (32,347)  
Ending balance 370,088 351,379 376,458
Funded status (87,317) (100,597)  
Accrued benefit cost at end of period (87,317) (100,597)  
Black Lung      
Change in benefit obligation:      
Accumulated benefit obligation at beginning of period 116,956 109,871  
Service cost 2,141 2,404 2,051
Interest cost 5,852 5,229 4,660
Actuarial loss (gain) 18,865 9,086  
Benefits paid (10,435) (9,634)  
Accumulated benefit obligation at end of period 133,379 116,956 109,871
Change in fair value of plan assets:      
Beginning balance 2,683 2,613  
Actual return on plan assets 87 70  
Employer contributions 10,435 9,634  
Benefits paid (10,435) (9,634)  
Ending balance 2,770 2,683 $ 2,613
Funded status (130,609) (114,273)  
Accrued benefit cost at end of period $ (130,609) $ (114,273)  
v3.25.4
Employee Benefit Plans - Gross Amounts Recognized in Accumulated Other Comprehensive (Income) Loss (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Pension Plan    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Net actuarial loss $ 31,053 $ 32,545
Black Lung    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Net actuarial loss $ 33,341 $ 18,814
v3.25.4
Employee Benefit Plans - Components of Net Periodic Benefit Cost (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Pension Plan      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Interest cost $ 23,254 $ 23,672 $ 23,973
Expected return on plan assets (19,673) (20,913) (21,996)
Amortization of net actuarial loss (gain) 1,597 1,764 730
Net periodic benefit (credit) 5,178 4,523 2,707
Black Lung      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Service cost 2,141 2,404 2,051
Interest cost 5,852 5,229 4,660
Expected return on plan assets (54) (52) (50)
Amortization of net actuarial loss (gain) 4,305 2,884 (2,833)
Net periodic benefit (credit) $ 12,244 $ 10,465 $ 3,828
v3.25.4
Employee Benefit Plans - Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive (Loss) Income (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Actuarial loss (gain) $ 18,880 $ 16,659 $ 34,205
Amortization of net actuarial (loss) gain (5,645) (4,457) 2,324
Pension Plan      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Actuarial loss (gain) 105 8,250 14,106
Amortization of net actuarial (loss) gain (1,597) (1,764) (730)
Total recognized in other comprehensive income (1,492) 6,486 13,376
Black Lung      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Actuarial loss (gain) 18,832 9,068 19,995
Amortization of net actuarial (loss) gain (4,305) (2,884) 2,833
Total recognized in other comprehensive income $ 14,527 $ 6,184 $ 22,828
v3.25.4
Employee Benefit Plans - Plans with Benefit Obligations in Excess of Plan Assets (Details) - Pension Plan - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Defined Benefit Plan Disclosure [Line Items]    
Projected benefit obligation $ 457,405 $ 451,976
Accumulated benefit obligation 457,405 451,976
Fair value of plan assets $ 370,088 $ 351,379
v3.25.4
Employee Benefit Plans - Assumptions Used (Details)
3 Months Ended 12 Months Ended
Jun. 30, 2024
Mar. 31, 2024
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Pension Plan          
Weighted-Average Assumptions to Determine Benefit Obligations          
Discount rate     5.44% 5.65%  
Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost          
Discount rate for benefit obligation     5.65% 5.12% 5.42%
Discount rate for interest cost     5.33% 4.99% 5.27%
Expected return on plan assets 5.70% 6.20% 5.70% 5.70% 6.20%
Pension Plan | Equity securities          
Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost          
Target allocation (as a percent)     50.00%    
Pension Plan | Fixed income funds          
Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost          
Target allocation (as a percent)     50.00%    
Black Lung          
Weighted-Average Assumptions to Determine Benefit Obligations          
Discount rate     5.46% 5.66%  
Federal black lung income benefit trend rate     2.50% 2.50%  
Federal black lung medical benefit trend rate     5.00% 5.00%  
Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost          
Discount rate for benefit obligation     5.66% 5.13% 5.42%
Discount rate for service cost     5.88% 5.31% 5.58%
Discount rate for interest cost     5.27% 4.98% 5.23%
Federal black lung income benefit trend rate     2.50% 2.50% 2.50%
Federal black lung medical benefit trend rate     5.00% 5.00% 5.00%
Expected return on plan assets     2.00% 2.00% 2.00%
v3.25.4
Employee Benefit Plans - Allocation of Plan Assets (Details) - Pension Plan
Dec. 31, 2026
Dec. 31, 2025
Defined Benefit Plan Disclosure [Line Items]    
Percentage of Plan Assets   100.00%
Forecast    
Defined Benefit Plan Disclosure [Line Items]    
Target Allocation Percentage 100.00%  
Equity securities    
Defined Benefit Plan Disclosure [Line Items]    
Target Allocation Percentage   50.00%
Percentage of Plan Assets   50.00%
Equity securities | Forecast    
Defined Benefit Plan Disclosure [Line Items]    
Target Allocation Percentage 50.00%  
Fixed income funds    
Defined Benefit Plan Disclosure [Line Items]    
Target Allocation Percentage   50.00%
Percentage of Plan Assets   44.00%
Fixed income funds | Forecast    
Defined Benefit Plan Disclosure [Line Items]    
Target Allocation Percentage 50.00%  
Other    
Defined Benefit Plan Disclosure [Line Items]    
Percentage of Plan Assets   6.00%
Other | Forecast    
Defined Benefit Plan Disclosure [Line Items]    
Target Allocation Percentage 0.00%  
v3.25.4
Employee Benefit Plans - Estimated Cash Payments (Details)
$ in Thousands
Dec. 31, 2025
USD ($)
Pension Plan  
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]  
2026 $ 31,937
2027 31,822
2028 31,526
2029 31,236
2030 30,964
2031-2035 152,532
Estimated future cash payments 310,017
Black Lung  
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]  
2026 12,329
2027 12,200
2028 11,960
2029 11,769
2030 11,703
2031-2035 33,695
Estimated future cash payments $ 93,656
v3.25.4
Employee Benefit Plans - Fair Value of Plan Assets (Details) - Pension Plan - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets $ 370,088 $ 351,379 $ 376,458
Level 3      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets   12,488 $ 12,230
Defined Benefit Plan, Assets After Cash and Receivables for Investments Sold      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 370,088 351,379  
Cash & cash equivalents      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 8,931    
Receivable      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 2,143 1,245  
Defined Benefit Plan, Assets Before Cash and Receivables for Investments Sold | Total      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 359,014 350,134  
Defined Benefit Plan, Assets Before Cash and Receivables for Investments Sold | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 184,580 0  
Defined Benefit Plan, Assets Before Cash and Receivables for Investments Sold | Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 161,542 337,198  
Defined Benefit Plan, Assets Before Cash and Receivables for Investments Sold | Level 3      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 12,488 12,488  
Defined Benefit Plan, Assets Before Cash and Receivables for Investments Sold | Assets Measured at NAV      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 404 448  
ETF Funds | Total      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 97,401    
ETF Funds | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 97,401    
ETF Funds | Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0    
ETF Funds | Level 3      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0    
ETF Funds | Assets Measured at NAV      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0    
Mutual funds | Total      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 87,179    
Mutual funds | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 87,179    
Mutual funds | Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0    
Mutual funds | Level 3      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0    
Mutual funds | Assets Measured at NAV      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0    
Multi-asset fund | Total      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets   170,829  
Multi-asset fund | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets   0  
Multi-asset fund | Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets   170,829  
Multi-asset fund | Level 3      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets   0  
Multi-asset fund | Assets Measured at NAV      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets   0  
Corporate bonds | Total      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 92,076    
Corporate bonds | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0    
Corporate bonds | Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 92,076    
Corporate bonds | Level 3      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0    
Corporate bonds | Assets Measured at NAV      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0    
U.S. government securities | Total      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 68,270    
U.S. government securities | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0    
U.S. government securities | Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 68,270    
U.S. government securities | Level 3      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0    
U.S. government securities | Assets Measured at NAV      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0    
Bond fund | Total      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets   165,100  
Bond fund | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets   0  
Bond fund | Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets   165,100  
Bond fund | Level 3      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets   0  
Bond fund | Assets Measured at NAV      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets   0  
Commingled short-term fund | Total      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 1,196 1,269  
Commingled short-term fund | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0 0  
Commingled short-term fund | Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 1,196 1,269  
Commingled short-term fund | Level 3      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0 0  
Commingled short-term fund | Assets Measured at NAV      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0 0  
Private equity funds | Total      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 404 448  
Private equity funds | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0 0  
Private equity funds | Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0 0  
Private equity funds | Level 3      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0 0  
Private equity funds | Assets Measured at NAV      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 404 448  
Guaranteed insurance contract | Total      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 12,488 12,488  
Guaranteed insurance contract | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0 0  
Guaranteed insurance contract | Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 0 0  
Guaranteed insurance contract | Level 3      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets 12,488 12,488  
Guaranteed insurance contract | Assets Measured at NAV      
Defined Benefit Plan Disclosure [Line Items]      
Total plan assets $ 0 $ 0  
v3.25.4
Employee Benefit Plans - Changes in Level 3 Assets (Details) - Pension Plan
$ in Thousands
12 Months Ended
Dec. 31, 2024
USD ($)
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]  
Beginning balance $ 376,458
Ending balance 351,379
Level 3  
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]  
Beginning balance 12,230
Relating to assets still held at the reporting date 524
Purchases, sales and settlements (266)
Ending balance $ 12,488
v3.25.4
Employee Benefit Plans - Workers' Compensation (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Retirement Benefits [Abstract]    
Current liabilities $ 8,880 $ 9,444
Long-term liabilities 72,685 79,897
Total liabilities 81,565 89,341
Less expected insurance receivable (31,947) (35,891)
Workers’ compensation obligations, net of expected insurance receivables $ 49,618 $ 53,450
v3.25.4
Employee Benefit Plans - Amounts Recognized in Balance Sheet (Details) - Black Lung - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Accrued benefit cost at end of period $ 130,609 $ 114,273
Current liabilities    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Accrued benefit cost at end of period 12,329 11,209
Long-term liabilities    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Accrued benefit cost at end of period $ 118,280 $ 103,064
v3.25.4
Stock-Based Compensation Awards - Narrative (Details)
$ / shares in Units, $ in Thousands
12 Months Ended
Feb. 29, 2024
director
Dec. 31, 2025
USD ($)
award_type
$ / shares
shares
Dec. 31, 2024
USD ($)
$ / shares
shares
Dec. 31, 2023
USD ($)
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of award types | award_type   2    
Stock compensation expense | $   $ 13,640 $ 12,929 $ 20,856
Restricted stock units | Board | Executive Chair of the Board        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Incremental compensation cost | $       6,717
Time-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted   50,335    
Grant date fair value (in dollars per share) | $ / shares   $ 185.77    
Unrecognized compensation cost of non-vested shares | $   $ 4,526    
Unrecognized compensation cost, period for recognition   1 year 4 months 28 days    
Total fair value of vested shares | $   $ 5,907 $ 31,257 $ 35,204
Operational performance-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted   18,168    
Grant date fair value (in dollars per share) | $ / shares   $ 196.42    
Potential distribution of shares (as a percent)   100.00% 100.00% 100.00%
Unrecognized compensation cost of non-vested shares | $   $ 801    
Unrecognized compensation cost, period for recognition   1 year 2 months 12 days    
Total fair value of vested shares | $   $ 2,406 $ 40,270 $ 5,339
Relative performance-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted   12,111    
Grant date fair value (in dollars per share) | $ / shares   $ 231.59 $ 531.08 $ 267.18
Unrecognized compensation cost of non-vested shares | $   $ 3,052    
Unrecognized compensation cost, period for recognition   1 year 7 months 24 days    
Total fair value of vested shares | $   $ 2,303 $ 26,847 $ 3,559
Selling, General and Administrative Expenses        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock-based compensation expense (as a percent)   85.00% 86.00% 95.00%
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   113,884    
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   765,333    
LTIP | Restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of directors granted with awards | director 2      
LTIP | Time-based restricted stock units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted   50,335 25,734 35,018
Grant date fair value (in dollars per share) | $ / shares   $ 185.77 $ 389.07 $ 165.43
Vesting period   3 years 3 years 3 years
LTIP | Performance-based restricted stock units | Employee        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted   30,279 15,820 49,701
Vesting period   3 years 3 years 3 years
LTIP | Performance-based restricted stock units | Employee | Minimum        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Potential distribution of shares (as a percent)   0.00% 0.00% 0.00%
LTIP | Performance-based restricted stock units | Employee | Maximum        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Potential distribution of shares (as a percent)   200.00% 200.00% 200.00%
LTIP | Operational performance-based restricted stock units | Employee        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted   18,168 9,490 29,816
Grant date fair value (in dollars per share) | $ / shares   $ 196.42 $ 400.93 $ 171.07
LTIP | Relative performance-based restricted stock units | Employee        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted   12,111 6,330 19,885
LTIP | Relative performance-based restricted stock units | Employee | Closing Stock Price on Trading Day Before Grant Date        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted       2,093
Grant date fair value (in dollars per share) | $ / shares       $ 171.07
LTIP | Relative performance-based restricted stock units | Employee | Monte Carlo Simulation        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of share awards granted       17,792
MIP and LTIP        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Shares repurchased (in shares)   26,519 144,427 81,287
Common stock repurchases and related expenses | $   $ 5,155 $ 55,419 $ 17,333
Share repurchase price (in dollars per share) | $ / shares   $ 194.39 $ 383.72 $ 213.23
v3.25.4
Stock-Based Compensation Awards - Award Activity (Details) - $ / shares
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Time-based restricted stock units      
Number of  Shares      
Beginning balance (in shares) 43,330    
Granted (in shares) 50,335    
Vested (in shares) (31,276)    
Forfeited/Canceled (in shares) (1,025)    
Ending balance (in shares) 61,364 43,330  
Weighted-Average Grant  Date Fair Value      
Beginning balance (in dollars per share) $ 252.62    
Granted (in dollars per share) 185.77    
Vested (in dollars per share) 175.00    
Forfeited/Canceled (in dollars per share) 249.49    
Ending balance (in dollars per share) $ 237.40 $ 252.62  
Restricted stock units and deferred settlements      
Number of  Shares      
Vested (in shares) (8,071)    
Relative performance-based restricted stock units      
Number of  Shares      
Beginning balance (in shares) 33,378    
Granted (in shares) 12,111    
Vested (in shares) (11,879)    
Forfeited/Canceled (in shares) (523)    
Ending balance (in shares) 33,087 33,378  
Weighted-Average Grant  Date Fair Value      
Beginning balance (in dollars per share) $ 251.61    
Granted (in dollars per share) 231.59 $ 531.08 $ 267.18
Vested (in dollars per share) 97.33    
Forfeited/Canceled (in dollars per share) 297.20    
Ending balance (in dollars per share) $ 298.95 $ 251.61  
Relative performance-based restricted stock units above 100% of targeted performance level      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Target performance level (as a percent) 100.00% 100.00% 100.00%
Number of  Shares      
Vested (in shares) (10,244)    
Operational performance-based restricted stock units      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Target performance level (as a percent) 100.00% 100.00% 100.00%
Number of  Shares      
Beginning balance (in shares) 50,054    
Granted (in shares) 18,168    
Vested (in shares) (12,410)    
Forfeited/Canceled (in shares) (6,193)    
Ending balance (in shares) 49,619 50,054  
Weighted-Average Grant  Date Fair Value      
Beginning balance (in dollars per share) $ 170.75    
Granted (in dollars per share) 196.42    
Vested (in dollars per share) 60.37    
Forfeited/Canceled (in dollars per share) 79.77    
Ending balance (in dollars per share) $ 219.11 $ 170.75  
Operational performance-based restricted stock units above 100% target performance level      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Target performance level (as a percent) 100.00%    
Number of  Shares      
Vested (in shares) (5,075)    
v3.25.4
Stock-Based Compensation Awards - Valuation Assumptions (Details)
12 Months Ended
Dec. 31, 2025
$ / shares
Dec. 31, 2024
d
$ / shares
Dec. 31, 2023
d
$ / shares
Dec. 31, 2022
d
$ / shares
Dec. 31, 2021
d
Relative performance-based restricted stock units          
Share-based Payment Award          
Weighted average grant date fair value (in dollars per share) $ 231.59 $ 531.08 $ 267.18    
Start price (in dollars per share) 216.98 316.88 151.35    
Valuation date stock price (in dollars per share) $ 193.40 $ 389.97 $ 176.44    
Expected volatility (as a percent) 57.69% 64.21% 102.06%    
Risk-free interest rate (as a percent) 4.29% 4.16% 3.82%    
Expected dividend yield (as a percent) 0.00% 0.00% 0.00%    
Cash-based Payment Award          
Average closing stock price, threshold trading days | d   20 20 20  
Performance-based cash incentive awards          
Cash-based Payment Award          
Weighted average grant date fair value (as a percent)       61.97%  
Start price (in dollars per share)       $ 53.29  
Valuation date stock price (in dollars per share)       $ 61.09  
Expected volatility (as a percent)       106.48%  
Risk-free interest rate (as a percent)       1.26%  
Expected divided yield (as a percent)       0.00%  
Average closing stock price, threshold trading days | d         20
v3.25.4
Stock-Based Compensation Awards - Performance-Based Cash Incentive Awards (Details) - Performance-based cash incentive awards
$ in Thousands
12 Months Ended
Dec. 31, 2025
USD ($)
Target Dollar Value  
Non-vested awards outstanding at December 31, 2024 $ 990
Granted 0
Vested (990)
Forfeited 0
Non-vested awards outstanding at December 31, 2025 $ 0
Weighted-Average Fair Value as a % of Target Dollar Value  
Non-vested awards outstanding at December 31, 2024 (as a percent) 186.23%
Granted (as a percent) 0.00%
Vested (as a percent) 186.23%
Forfeited (as a percent) 0.00%
Non-vested awards outstanding at December 31, 2025 (as a percent) 0.00%
v3.25.4
Related Party Transactions (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Related Party Transactions [Abstract]    
Amount of related party transactions $ 0 $ 0
v3.25.4
Commitments and Contingencies - Narrative (Details)
tonOfCoal in Thousands, $ in Thousands
1 Months Ended 12 Months Ended
Apr. 30, 2024
tonOfCoal
Dec. 31, 2025
USD ($)
Dec. 31, 2024
USD ($)
Dec. 31, 2023
USD ($)
Jan. 31, 2025
USD ($)
Long-term Purchase Commitment [Line Items]          
Arrangement, term 3 years        
Surety bond          
Long-term Purchase Commitment [Line Items]          
Outstanding surety bonds   $ 170,014      
Reclamation-related obligations | Collateral Pledged          
Long-term Purchase Commitment [Line Items]          
Restricted cash, restricted investments and deposits   28,197      
ABL Facility          
Long-term Purchase Commitment [Line Items]          
Letters of credit outstanding   41,254 $ 42,149    
Minimum          
Long-term Purchase Commitment [Line Items]          
Number of tons of coal allowed to be loaded | tonOfCoal 1,200        
Minimum | Black lung benefit expense inflation rate          
Long-term Purchase Commitment [Line Items]          
Collateral for black lung obligations         $ 80,000
Maximum          
Long-term Purchase Commitment [Line Items]          
Number of tons of coal allowed to be loaded | tonOfCoal 2,000        
Maximum | Black lung benefit expense inflation rate          
Long-term Purchase Commitment [Line Items]          
Collateral for black lung obligations         $ 100,000
Coal purchase agreements          
Long-term Purchase Commitment [Line Items]          
Purchase commitment   11,072      
Coal transportation agreements          
Long-term Purchase Commitment [Line Items]          
Minimum obligation, 2026   117,517      
Minimum obligation, 2027   53,633      
Minimum obligation, 2028   14,246      
Minimum obligation, 2029   14,667      
Minimum obligation, 2030   3,693      
Coal transportation agreements | DTA          
Long-term Purchase Commitment [Line Items]          
Minimum obligation, 2026   39,618      
Additional DTA investment          
Long-term Purchase Commitment [Line Items]          
Minimum obligation, 2026   21,000      
Minimum obligation, 2027   21,000      
Minimum obligation, 2028   21,000      
Minimum obligation, 2029   21,000      
Minimum obligation, 2030   21,000      
Coal          
Long-term Purchase Commitment [Line Items]          
Coal royalty expense   103,035 $ 141,812 $ 185,398  
Coal | Royalty obligations          
Long-term Purchase Commitment [Line Items]          
Minimum obligation, 2026   16,859      
Minimum obligation, 2027   16,163      
Minimum obligation, 2028   15,104      
Minimum obligation, 2029   13,745      
Minimum obligation, 2030   13,642      
Minimum obligation, after 2030   $ 99,215      
v3.25.4
Commitments and Contingencies - Restricted Cash (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Long-term Purchase Commitment [Line Items]    
Total long-term restricted cash $ 126,911 $ 122,583
Workers’ compensation and black lung obligations    
Long-term Purchase Commitment [Line Items]    
Total long-term restricted cash 117,150 113,144
Reclamation-related obligations    
Long-term Purchase Commitment [Line Items]    
Total long-term restricted cash 959 697
Financial payments and other performance obligations    
Long-term Purchase Commitment [Line Items]    
Total long-term restricted cash $ 8,802 $ 8,742
v3.25.4
Commitments and Contingencies - Restricted Investments (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Long-term Purchase Commitment [Line Items]    
Total restricted investments $ 34,356 $ 43,131
Worker's compensation    
Long-term Purchase Commitment [Line Items]    
Total restricted investments 3,172 3,119
Reclamation-related obligations    
Long-term Purchase Commitment [Line Items]    
Total restricted investments 27,238 34,018
Financial payments and other performance obligations    
Long-term Purchase Commitment [Line Items]    
Total restricted investments $ 3,946 $ 5,994
v3.25.4
Commitments and Contingencies - Cash Deposits Held by Third Parties (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Long-term Purchase Commitment [Line Items]    
Total deposits $ 4,792 $ 4,974
Less current portion 0 (21)
Total deposits, net of current portion 4,792 4,953
Workers’ compensation obligations    
Long-term Purchase Commitment [Line Items]    
Total deposits 4,108 4,108
Other operating agreements    
Long-term Purchase Commitment [Line Items]    
Total deposits $ 684 $ 866
v3.25.4
Concentration of Credit Risk and Major Customer (Details)
$ in Thousands
12 Months Ended
Dec. 31, 2025
USD ($)
customer
Dec. 31, 2024
USD ($)
customer
Dec. 31, 2023
USD ($)
customer
Concentration Risk [Line Items]      
Coal revenues $ 2,122,605 $ 2,946,579 $ 3,456,630
Revenues 2,129,481 2,957,285 3,471,417
Met coal      
Concentration Risk [Line Items]      
Coal revenues 2,030,460 2,846,542 3,278,627
Thermal coal      
Concentration Risk [Line Items]      
Coal revenues 92,145 100,037 178,003
Export Coal Revenue      
Concentration Risk [Line Items]      
Coal revenues $ 1,557,086 $ 2,309,777 $ 2,539,068
Revenues | Customer Concentration Risk      
Concentration Risk [Line Items]      
Number of customers | customer 3 2 2
Revenues | Customer Concentration Risk | Top Customer      
Concentration Risk [Line Items]      
Concentration risk (as a percent) 14.00% 16.00% 13.00%
Revenues | Customer Concentration Risk | Top 10 Customers      
Concentration Risk [Line Items]      
Concentration risk (as a percent) 77.00% 75.00% 74.00%
Revenues | Geographic Concentration Risk | Domestic Coal Revenue      
Concentration Risk [Line Items]      
Concentration risk (as a percent) 27.00% 22.00% 26.00%
Revenues | Geographic Concentration Risk | Export Coal Revenue      
Concentration Risk [Line Items]      
Concentration risk (as a percent) 73.00% 78.00% 74.00%
Accounts Receivable | Customer Concentration Risk      
Concentration Risk [Line Items]      
Number of customers | customer 4 2 3
Coal Sales Volume | Product Concentration Risk | Met coal      
Concentration Risk [Line Items]      
Concentration risk (as a percent) 93.00% 93.00% 90.00%
Coal Sales Volume | Product Concentration Risk | Thermal coal      
Concentration Risk [Line Items]      
Concentration risk (as a percent) 7.00% 7.00% 10.00%
v3.25.4
Segment Information - Narrative (Details)
12 Months Ended
Dec. 31, 2025
segment
mine
Segment Reporting [Abstract]  
Number of reportable segments 1
Number of operating segments 1
Number of active mines | mine 6
v3.25.4
Segment Information - Schedule of Segment Results (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Segment Reporting Information [Line Items]      
Coal revenues $ 2,122,605 $ 2,946,579 $ 3,456,630
Other revenues 6,876 10,706 14,787
Total revenues 2,129,481 2,957,285 3,471,417
Cost of coal sales (exclusive of items shown separately below) 1,924,691 2,451,601 2,356,138
Depreciation, depletion and amortization 174,524 167,331 136,869
Accretion on asset retirement obligations 22,126 25,050 25,500
Amortization of acquired intangibles 5,427 6,700 8,523
Selling, general and administrative expenses 60,158 74,000 82,390
Interest expense 3,019 3,811 6,923
Interest income (15,466) (18,208) (11,933)
Equity loss in affiliates 24,867 20,302 18,263
Income tax (benefit) expense (25,772) 23,171 123,503
Net (loss) income (61,687) 187,579 721,956
Operating segments | Met      
Segment Reporting Information [Line Items]      
Coal revenues 2,122,605 2,946,579 3,406,643
Other revenues 6,876 10,706 14,787
Total revenues 2,129,481 2,957,285 3,421,430
Non-GAAP Cost of coal sales 1,562,012 1,918,427 1,847,363
Freight and handling costs 333,691 503,306 438,783
Idled and closed mine costs 28,988 29,868 18,579
Cost of coal sales (exclusive of items shown separately below) 1,924,691 2,451,601 2,304,725
Depreciation, depletion and amortization 174,524 167,331 127,721
Accretion on asset retirement obligations 22,126 25,050 15,471
Amortization of acquired intangibles 5,427 6,700 8,523
Selling, general and administrative expenses 60,158 74,000 81,321
Interest expense 3,019 3,811 6,923
Interest income (15,466) (18,208) (11,933)
Equity loss in affiliates 24,867 20,302 18,263
Other segment items 17,594 15,948 3,284
Income tax (benefit) expense (25,772) 23,171 126,669
Total other expenses 266,477 318,105 376,242
Net (loss) income $ (61,687) $ 187,579 $ 740,463
v3.25.4
Segment Information - Reconciliation of Segment Items to Consolidated (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Segment Reporting Information [Line Items]      
Revenues $ 2,129,481 $ 2,957,285 $ 3,471,417
Depreciation, depletion and amortization 174,524 167,331 136,869
Accretion on asset retirement obligations 22,126 25,050 25,500
Income tax (benefit) expense (25,772) 23,171 123,503
Net (loss) income (61,687) 187,579 721,956
Operating Segments | Met      
Segment Reporting Information [Line Items]      
Revenues 2,129,481 2,957,285 3,421,430
Depreciation, depletion and amortization 174,524 167,331 127,721
Accretion on asset retirement obligations 22,126 25,050 15,471
Income tax (benefit) expense (25,772) 23,171 126,669
Net (loss) income $ (61,687) $ 187,579 740,463
Other Operating Segments and Intersegment Eliminations      
Segment Reporting Information [Line Items]      
Revenues     49,987
Depreciation, depletion and amortization     9,148
Accretion on asset retirement obligations     10,029
Income tax (benefit) expense     (3,166)
Net (loss) income     $ (18,507)