COMPASS MINERALS INTERNATIONAL INC, 10-Q filed on 2/7/2023
Quarterly Report
v3.22.4
Cover Page - shares
 3 Months Ended
Dec. 31, 2022
Feb. 03, 2023
Cover [Abstract]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Dec. 31, 2022  
Document Transition Report false  
Entity File Number 001-31921  
Entity Registrant Name Compass Minerals International, Inc.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 36-3972986  
Entity Address, Address Line One 9900 West 109th Street  
Entity Address, Address Line Two Suite 100  
Entity Address, City or Town Overland Park  
Entity Address, State or Province KS  
Entity Address, Postal Zip Code 66210  
City Area Code 913  
Local Phone Number 344-9200  
Title of 12(b) Security Common stock, $0.01 par value  
Trading Symbol CMP  
Security Exchange Name NYSE  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Common Stock, Shares Outstanding   41,098,585
Entity Central Index Key 0001227654  
Current Fiscal Year End Date --09-30  
Document Fiscal Year Focus 2023  
Document Fiscal Period Focus Q1  
Amendment Flag false  
Entity Shell Company false  
v3.22.4
CONSOLIDATED BALANCE SHEETS - USD ($)
$ in Millions
Dec. 31, 2022
Sep. 30, 2022
Current assets:    
Cash and cash equivalents $ 146.1 $ 46.1
Receivables, less allowance for doubtful accounts of $3.8 at December 31, 2022 and $3.4 at September 30, 2022 202.2 167.2
Inventories 301.0 304.4
Other 35.4 44.3
Total current assets 684.7 562.0
Property, plant and equipment, net 774.8 776.6
Intangible assets, net 45.3 45.4
Goodwill 56.8 56.4
Equity method investments 45.7 46.6
Other 157.4 156.5
Total assets 1,764.7 1,643.5
Current liabilities:    
Current portion of long-term debt 0.0 0.0
Accounts payable 113.4 114.7
Accrued salaries and wages 15.4 22.2
Income taxes payable 6.6 1.0
Accrued interest 8.5 14.1
Accrued expenses and other current liabilities 74.8 81.1
Total current liabilities 218.7 233.1
Long-term debt, net of current portion 832.1 947.6
Deferred income taxes, net 59.2 63.4
Other noncurrent liabilities 144.9 143.0
Commitments and contingencies (Note 10)
Stockholders’ equity:    
Common stock: $0.01 par value, 200,000,000 authorized shares; 42,197,964 issued shares at December 31, 2022 and 35,367,264 issued shares at September 30, 2022 0.4 0.4
Additional paid-in capital 403.4 152.1
Treasury stock, at cost — 1,174,077 shares at December 31, 2022 and 1,196,300 shares at September 30, 2022 (7.6) (7.3)
Retained earnings 219.9 226.5
Accumulated other comprehensive loss (106.3) (115.3)
Total stockholders’ equity 509.8 256.4
Total liabilities and stockholders’ equity $ 1,764.7 $ 1,643.5
v3.22.4
CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)
$ in Millions
Dec. 31, 2022
Sep. 30, 2022
ASSETS    
Allowance for doubtful accounts $ 3.8 $ 3.4
Stockholders’ equity:    
Common stock, par or stated value per share (in dollars per share) $ 0.01 $ 0.01
Common stock, shares authorized (in shares) 200,000,000 200,000,000
Common stock, shares issued (in shares) 42,197,964 35,367,264
Treasury stock, shares (in shares) 1,174,077 1,196,300
v3.22.4
CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($)
shares in Thousands, $ in Millions
 3 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Sales $ 352.4 $ 331.5
Gross profit 70.0 59.9
Selling, general and administrative expenses 42.1 39.5
Operating earnings 27.9 20.4
Other (income) expense:    
Interest income (1.1) (0.3)
Interest expense 13.9 13.9
Loss (gain) on foreign exchange 2.5 (0.4)
Net loss in equity investee 0.9 0.4
Other expense, net 0.1 0.1
Earnings from continuing operations before income taxes 11.6 6.7
Income tax expense (benefit) from continuing operations 11.9 (1.2)
Net (loss) earnings from continuing operations (0.3) 7.9
Net loss from discontinued operations 0.0 (5.5)
Net (loss) earnings $ (0.3) $ 2.4
Basic net (loss) earnings from continuing operations per common share (in dollars per share) $ (0.01) $ 0.23
Basic net loss from discontinued operations per common share (in dollars per share) 0 (0.16)
Basic net (loss) earnings per common share (in dollars per share) (0.01) 0.07
Diluted net (loss) earnings from continuing operations per common share (in dollars per share) (0.01) 0.23
Diluted net loss from discontinued operations per common share (in dollars per share) 0 (0.16)
Diluted net (loss) earnings per common share (in dollars per share) $ (0.01) $ 0.07
Weighted-average common shares outstanding (in thousands):    
Basic (in shares) 39,751 34,060
Diluted (in shares) 39,751 34,089
Shipping and handling cost    
Cost $ 107.4 $ 95.7
Product cost    
Cost $ 175.0 $ 175.9
v3.22.4
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($)
$ in Millions
 3 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Statement of Comprehensive Income [Abstract]    
Net (loss) earnings $ (0.3) $ 2.4
Other comprehensive income (loss):    
Unrealized gain from change in pension obligations, net of tax of $0.0 for the three months ended December 31, 2022 and 2021 0.1 0.1
Unrealized loss on cash flow hedges, net of tax of $0.4 and $0.7 for the three months ended December 31, 2022 and 2021, respectively (2.8) (2.0)
Cumulative translation adjustment 11.7 (3.8)
Comprehensive income (loss) $ 8.7 $ (3.3)
v3.22.4
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Parenthetical) - USD ($)
$ in Millions
 3 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Statement of Comprehensive Income [Abstract]    
Unrealized gain from change in pension obligations, tax $ 0.0 $ 0.0
Unrealized gain (loss) on cash flow hedges, tax $ 0.4 $ 0.7
v3.22.4
CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($)
$ in Millions
Total
Common Stock
Additional Paid-In Capital
Treasury Stock
Retained Earnings
Accumulated Other Comprehensive Loss
Beginning balance at Sep. 30, 2021 $ 293.1 $ 0.4 $ 136.3 $ (5.5) $ 272.4 $ (110.5)
Increase (Decrease) in Stockholders' Equity [Roll Forward]            
Comprehensive (loss) income (3.3)       2.4 (5.7)
Dividends on common stock (5.3)   (0.1)   (5.2)  
Stock options exercised, net of shares withheld for taxes 0.2   0.2      
Stock-based compensation 3.3   3.3      
Ending balance at Dec. 31, 2021 288.0 0.4 139.7 (5.5) 269.6 (116.2)
Beginning balance at Sep. 30, 2022 256.4 0.4 152.1 (7.3) 226.5 (115.3)
Increase (Decrease) in Stockholders' Equity [Roll Forward]            
Comprehensive (loss) income 8.7       (0.3) 9.0
Dividends on common stock (6.3)       (6.3)  
Private placement of common stock 240.7   240.7      
Shares issued for stock units, net of shares withheld for taxes (0.3)     (0.3)    
Stock-based compensation 10.6   10.6      
Ending balance at Dec. 31, 2022 $ 509.8 $ 0.4 $ 403.4 $ (7.6) $ 219.9 $ (106.3)
v3.22.4
CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) - $ / shares
 3 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Statement of Stockholders' Equity [Abstract]    
Cash dividends per share (in dollars per share) $ 0.15 $ 0.15
v3.22.4
CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)
$ in Millions
 3 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Cash flows from operating activities:    
Net (loss) earnings $ (0.3) $ 2.4
Adjustments to reconcile net (loss) earnings to net cash flows provided by operating activities:    
Depreciation, depletion and amortization 23.9 28.3
Amortization of deferred financing costs 0.7 0.7
Stock-based compensation 10.6 3.3
Deferred income taxes (5.4) (1.4)
Unrealized foreign exchange loss 2.0 2.2
Loss on impairment of long-lived assets 0.0 8.4
Net loss in equity investee 0.9 0.4
Other, net 1.0 0.1
Changes in operating assets and liabilities:    
Receivables (34.0) (68.8)
Inventories 5.1 12.6
Other assets 10.4 (1.2)
Accounts payable and accrued expenses and other current liabilities (13.1) 2.7
Other liabilities 0.3 (4.0)
Net cash provided by (used in) operating activities 2.1 (14.3)
Net cash used in investing activities    
Capital expenditures (19.9) (14.5)
Investments in equity method investees 0.0 (28.2)
Other, net (0.2) 1.5
Net cash used in investing activities (20.1) (41.2)
Cash flows from financing activities:    
Proceeds from revolving credit facility borrowings 16.7 162.4
Principal payments on revolving credit facility borrowings (168.2) (122.8)
Proceeds from issuance of long-term debt 35.4 32.5
Principal payments on long-term debt 0.0 (3.3)
Net proceeds from private placement of common stock 240.7 0.0
Dividends paid (6.3) (5.3)
Proceeds from stock options exercised 0.0 0.2
Shares withheld to satisfy employee tax obligations (0.3) 0.0
Other, net (0.3) (0.4)
Net cash provided by financing activities 117.7 63.3
Effect of exchange rate changes on cash and cash equivalents 0.3 0.1
Net change in cash and cash equivalents 100.0 7.9
Cash and cash equivalents, beginning of the year 46.1 21.0
Cash and cash equivalents, end of period 146.1 28.9
Less: cash and cash equivalents included in current assets held for sale 0.0 (8.6)
Cash and cash equivalents of continuing operations, end of period 146.1 20.3
Supplemental cash flow information:    
Interest paid, net of amounts capitalized 18.8 18.6
Income taxes paid, net of refunds $ 2.0 $ 5.5
v3.22.4
Accounting Policies and Basis of Presentation
 3 Months Ended
Dec. 31, 2022
Accounting Policies [Abstract]  
Accounting Policies and Basis of Presentation Accounting Policies and Basis of Presentation:
Compass Minerals International, Inc. (“CMI”), through its subsidiaries (collectively, the “Company”), is a leading global provider of essential minerals focused on safely delivering where and when it matters to help solve nature’s challenges for customers and communities. The Company’s salt products help keep roadways safe during winter weather and are used in numerous other consumer, industrial, chemical and agricultural applications. Its plant nutrition business is the leading North American producer of sulfate of potash (“SOP”), which is used in the production of specialty fertilizers for high-value crops and turf and helps improve the quality and yield of crops, while supporting sustainable agriculture. The Company’s principal products are salt, consisting of sodium chloride and magnesium chloride, and SOP. Additionally, the Company is pursuing development of a sustainable lithium brine resource to support the North American battery market and is a minority owner of Fortress North America, LLC (“Fortress”), a next-generation fire retardant company. The Company’s production sites are located in the United States (“U.S.”), Canada and the United Kingdom (“U.K.”). The Company also provides records management services to businesses located in the U.K. Except where otherwise noted, references to North America include only the continental U.S. and Canada, and references to the U.K. include only England, Scotland and Wales. References to “Compass Minerals,” “our,” “us” and “we” refer to CMI and its consolidated subsidiaries.
 
CMI is a holding company with no significant operations other than those of its wholly-owned subsidiaries. The consolidated financial statements include the accounts of CMI and its wholly-owned domestic and foreign subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation.

The accompanying unaudited consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete consolidated financial statements. These unaudited consolidated financial statements should be read in conjunction with the consolidated financial statements of the Company for the annual period ended September 30, 2022, as filed with the Securities and Exchange Commission (the “SEC”) in its Annual Report on Form 10-K on December 14, 2022. In the opinion of management, all adjustments, consisting of normal recurring adjustments considered necessary for a fair presentation, have been included.
 
The Company experiences a substantial amount of seasonality in its sales, including its deicing salt product sales. As a result, Salt segment sales and operating income are generally higher in the first and second fiscal quarters (ending December 31 and March 31) and lower during the third and fourth fiscal quarters (ending June 30 and September 30) of each year. In particular, sales of highway and consumer deicing salt and magnesium chloride products vary based on the severity of the winter conditions in areas where the products are used. Following industry practice in North America and the U.K., the Company seeks to stockpile sufficient quantities of deicing salt throughout the first, third and fourth fiscal quarters (ending December 31, June 30 and September 30) to meet the estimated requirements for the winter season. Production of deicing salt can also vary based on the severity or mildness of the preceding winter season. Due to the seasonal nature of the deicing product lines, operating results for the interim periods are not necessarily indicative of the results that may be expected for the full fiscal year. The Company’s plant nutrition business is also seasonal. As a result, the Company and its customers generally build inventories during the plant nutrition business’ low demand periods of the year (which are typically winter and summer, but can vary due to weather and other factors) to ensure timely product availability during the peak sales seasons (which are typically spring and autumn, but can also vary due to weather and other factors).

Significant Accounting Policies

The Company’s significant accounting policies are detailed in “Note 2 – Summary of Significant Accounting Policies” within Part II, Item 8 of its Annual Report on Form 10-K for the annual period ended September 30, 2022. The Company reports its financial results from discontinued operations and continuing operations separately to recognize the financial impact of disposal transactions apart from ongoing operations. Discontinued operations reporting occurs when a component or a group of components of an entity has been disposed or classified as held for sale and represents a strategic shift that has a major effect on the entity’s operations and financial results. In the Company’s Consolidated Statements of Cash Flows, the cash flows from discontinued operations are not separately classified. Unless otherwise indicated, amounts provided in these Notes pertain to continuing operations. See Note 2 for information on discontinued operations and Note 11 for information on the Company’s reportable segments.
Recent Accounting Pronouncements

The Company has evaluated all of the recently issued, but not yet effective, accounting standards that have been issued or proposed by the Financial Accounting Standards Board or other standards-setting bodies through the filing date of these unaudited consolidated financial statements and does not believe the future adoption of any such pronouncements will have a material impact on its consolidated financial statements.

Strategic Evaluation and Plan to Sell Businesses

Following an evaluation of the strategic fit of certain of the Company’s businesses and subsequent restructuring of its former South American Plant Nutrition segment to enable separate sales processes for its chemicals and specialty plant nutrition businesses and equity investment in Fermavi Eletroquímica Ltda. (“Fermavi”), in fiscal 2021 the Company’s Board of Directors approved the plan to sell each of these businesses and the North America micronutrient business (the “Specialty Businesses”) with a goal of reducing the Company’s leverage and enabling increased focus on optimizing the Company’s core businesses.

The Company concluded that the sale of the Specialty Businesses represented a strategic shift for the Company that would have a material effect on its operations and financial results. Consequently, the Specialty businesses were reclassified as discontinued operations on the Consolidated Statements of Operations. See Note 2 for further discussion of the sales of these businesses.
Unless otherwise indicated, amounts provided in these Notes pertain to continuing operations.
v3.22.4
Discontinued Operations
 3 Months Ended
Dec. 31, 2022
Discontinued Operations and Disposal Groups [Abstract]  
Discontinued Operations Discontinued Operations:
During fiscal 2021 the Company sold its South America specialty plant nutrition business and equity investment in Fermavi and its North America micronutrient business. In connection with the sale of its South America specialty plant nutrition business the Company received net cash of approximately $318.4 million with an additional earnout payment of up to R$88 million Brazilian reais. On April 7, 2022, the Company received the maximum earnout possible under the terms of the sale, or $18.5 million based on exchange rates at the time of receipt.

Also in fiscal 2021, the Company completed the sale of its North America micronutrient business for approximately $56.7 million and its investment in Fermavi for R$45 million Brazilian reais (including R$30 million Brazilian reais of deferred purchase price). The Company received gross proceeds of approximately $2.9 million and recorded a discounted deferred proceeds receivable of approximately $4.8 million (based on exchange rates at the time of closing). As of December 31, 2022 approximately R$22.5 million Brazilian reais of deferred proceeds remains outstanding.

On April 20, 2022, the Company completed the sale of its South America chemicals business to a subsidiary of Cape Acquisitions LLC. Upon closing of the all-cash sale, the Company received gross proceeds of approximately $51.5 million based on exchange rates at the time of receipt, including a post-closing adjustment and compensation of $6.4 million for cash on hand that transferred to the buyer. The Company also paid fees of $2.4 million related to this sale. The Company recognized a loss recovery of $1.6 million during the three months ended June 30, 2022, an incremental loss from the sale of $23.1 million during the nine months ended June 30, 2022 and released $49.5 million from accumulated currency translation adjustment (“CTA”). The sale included all of the Company’s remaining operations in Brazil, concluding its previously announced plan to exit the South American market.

In measuring the assets and liabilities held for sale at fair value less estimated costs to sell, the Company completed an impairment analysis when its Board of Directors committed to a plan to sell the Specialty Businesses and the Company updated the analysis each quarter until each of the Specialty Businesses were sold.

The information below sets forth selected financial information related to the operating results of the Specialty Businesses classified as discontinued operations. The Specialty Businesses’ revenue and expenses have been reclassified to net earnings from discontinued operations in prior periods. The Consolidated Statements of Operations present the revenue and expenses that were reclassified from the specified line items to discontinued operations.
The following table represents summarized Consolidated Statements of Operations information of discontinued operations (in millions):

Three Months Ended
December 31,
2021
Sales$22.4 
Shipping and handling cost1.2 
Product cost10.9 
Gross profit10.3 
Selling, general and administrative expenses1.6 
Operating earnings8.7 
Loss on foreign exchange3.1 
Net loss on adjustment to fair value less estimated costs to sell8.4 
Other income, net(0.2)
Loss from discontinued operations before income taxes(2.6)
Income tax expense2.9 
Net loss from discontinued operations$(5.5)

The significant components included in the Company’s Consolidated Statements of Cash Flows for discontinued operations are as follows (in millions):

Three Months Ended
December 31,
2021
Loss on impairment of long-lived assets$8.4 
Capital expenditures(0.7)
v3.22.4
Revenues
 3 Months Ended
Dec. 31, 2022
Revenue from Contract with Customer [Abstract]  
Revenues Revenues:
Nature of Products and Services

The Company’s Salt segment products include salt and magnesium chloride for use in road deicing and dust control, food processing, water softening, and agricultural and industrial applications. The Company’s Plant Nutrition segment produces and markets SOP in various grades worldwide to distributors and retailers of crop inputs, as well as growers and for industrial uses. In the U.K., the Company operates a records management business utilizing excavated areas of its Winsford salt mine with one other location in London, England.

Identifying the Contract

The Company accounts for a customer contract when there is approval and commitment from both parties, the rights of the parties and payment terms are identified, the contract has commercial substance and collectability of consideration is probable.

Identifying the Performance Obligations

At contract inception, the Company assesses the goods and services it has promised to its customers and identifies a performance obligation for each promise to transfer to the customer a distinct good or service (or bundle of goods or services). Determining whether products and services are considered distinct performance obligations that should be accounted for separately or aggregated together may require significant judgment.
Identifying and Allocating the Transaction Price

The Company’s revenues are measured based on consideration specified in the customer contract, net of any sales incentives and amounts collected on behalf of third parties such as sales taxes. In certain cases, the Company’s customer contracts may include promises to transfer multiple products and services to a customer. For multiple-element arrangements, the Company generally allocates the transaction price to each performance obligation in proportion to its stand-alone selling price.

When Performance Obligations Are Satisfied

The vast majority of the Company’s revenues are recognized at a point in time when the performance obligations are satisfied based upon transfer of control of the product or service to a customer. To determine when the control of goods is transferred, the Company typically assesses, among other things, the shipping terms of the contract, as shipping is an indicator of transfer of control. Some of the Company’s products are sold when the control of the goods transfers to the customer at the time of shipment. There are also instances when the Company provides shipping services to deliver its products. Shipping and handling costs that occur before the customer obtains control of the goods are deemed to be fulfillment activities and are accounted for as fulfillment costs. The Company has made an accounting policy election to recognize any shipping and handling costs that are incurred after the customer obtains control of the goods as fulfillment costs which are accrued at the time of revenue recognition.

Significant Payment Terms

The customer contract states the final terms of the sale, including the description, quantity and price of each product or service purchased. Payment is typically due in full within 30 days of delivery. The Company does not adjust the consideration for the effects of a significant financing component if the Company expects, at contract inception, that the period between when the good or service is transferred to the customer and when the customer pays for that good or service will be one year or less.

Refunds, Returns and Warranties

The Company’s products are generally not sold with a right of return and the Company does not generally provide credits or incentives, which may be required to be accounted for as variable consideration when estimating the amount of revenue to be recognized. The Company uses historical experience to estimate accruals for refunds due to manufacturing or other defects.

See Note 11 for disaggregation of sales by segment, type and geographical region.
v3.22.4
Inventories
 3 Months Ended
Dec. 31, 2022
Inventory Disclosure [Abstract]  
Inventories Inventories:
 
Inventories consist of the following (in millions):
 December 31,
2022		September 30,
2022
Finished goods$242.3 $251.6 
Raw materials and supplies58.7 52.8 
Total inventories$301.0 $304.4 
v3.22.4
Property, Plant and Equipment, Net
 3 Months Ended
Dec. 31, 2022
Property, Plant and Equipment [Abstract]  
Property, Plant and Equipment, Net Property, Plant and Equipment, Net:
 
Property, plant and equipment, net, consists of the following (in millions):
 December 31,
2022		September 30,
2022
Land, buildings and structures, and leasehold improvements$543.0 $534.8 
Machinery and equipment1,058.2 1,026.3 
Office furniture and equipment56.9 56.8 
Mineral interests168.7 167.1 
Construction in progress48.0 64.3 
 1,874.8 1,849.3 
Less: accumulated depreciation and depletion(1,100.0)(1,072.7)
Property, plant and equipment, net$774.8 $776.6 
v3.22.4
Goodwill and Intangible Assets, Net
 3 Months Ended
Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]  
Goodwill and Intangible Assets, Net Goodwill and Intangible Assets, Net:
Amounts related to the Company’s amortization of intangible assets are as follows (in millions):
Three Months Ended
December 31,
20222021
Aggregate amortization expense$0.4 $0.4 
Amounts related to the Company’s goodwill are as follows (in millions):
December 31,
2022		September 30,
2022
Plant Nutrition$51.0 $50.9 
Other5.8 5.5 
Total$56.8 $56.4 
The change in goodwill between September 30, 2022, and December 31, 2022 was due to the impact from translating foreign-denominated amounts to U.S. dollars. As of December 31, 2022, there were no indicators necessitating an interim impairment test of the Company’s reporting units based on the Company’s review of operating performance, among other factors, for the relevant reporting units.
v3.22.4
Equity Method Investments
 3 Months Ended
Dec. 31, 2022
Equity Method Investments and Joint Ventures [Abstract]  
Equity Method Investments Equity Method Investments:
The Company uses the equity method of accounting for equity securities when it has significant influence or when it has more than a minor ownership interest or more than minor influence over an investee’s operations but does not have a controlling financial interest. Initial investments are recorded at cost (including certain transaction costs) and are adjusted by the Company’s share of the investees’ undistributed earnings and losses. The Company may recognize its share of an investee’s earnings on a lag, if an investee’s financial results are not available in a timely manner.

For certain of the Company's equity method investments, such as investments where the capital structure of the equity investment results in different liquidation rights and priorities than what is reflected by the underlying percentage ownership interests, the Company's proportionate share of net earnings is accounted for using the Hypothetical Liquidation at Book Value ("HLBV") methodology available under the equity method of accounting. When applying HLBV, the Company determines the amount that would be received if the investee were to liquidate all of its assets and distribute the resulting cash to the investors based on contractually defined liquidation priorities, assuming the net assets were liquidated at their net book value.

The Company evaluates its equity method investments for impairment whenever events or changes in circumstances indicate that the carrying amounts of such investments may not be recoverable.
On November 2, 2021, the Company announced an investment in Fortress, a next-generation fire retardant business dedicated to developing and producing a portfolio of magnesium chloride-based fire retardant products to help combat wildfires. As of December 31, 2022, the Company has invested $50 million in Fortress in exchange for an ownership interest of approximately 45%. Under the HLBV methodology available under the equity method of accounting, the Company reflects its share of the income or loss of Fortress, net of tax, in its results each period on a one quarter reporting lag. The Company recorded $0.5 million and $0.1 million for its share of Fortress’ net losses in the three months ended December 31, 2022 and 2021, respectively.

The carrying value of the Company’s equity investment in Fortress is in excess of its share of Fortress’s net book value by approximately $27 million as of December 31, 2022. The basis difference primarily represents incremental value attributable to intangible assets and goodwill that has not been recognized in the financial statements of Fortress. The Company has liquidation preference under the terms of Fortress’ LLC agreement. Additionally, the Company has the right to purchase units from other Fortress unit holders and the right of first refusal to purchase all or any portion of any available Fortress units, both subject to certain conditions.

The balance of the Company’s net investment in Fortress of $45.3 million and $45.8 million as of December 31, 2022 and September 30, 2022, respectively is recorded in equity method investments in the Consolidated Balance Sheets. The Company also has other immaterial equity investments of $0.4 million and $0.8 million as of December 31, 2022 and September 30, 2022, respectively, for which it has recorded $0.4 million and $0.3 million for its share of losses in the three months ended December 31, 2022 and 2021, respectively.
v3.22.4
Income Taxes
 3 Months Ended
Dec. 31, 2022
Income Tax Disclosure [Abstract]  
Income Taxes Income Taxes:
The Company’s effective income tax rate differs from the U.S. statutory federal income tax rate primarily due to U.S. statutory depletion, state income taxes (net of federal tax benefit), nondeductible executive compensation over $1 million, foreign income, mining and withholding taxes, base erosion and anti-abuse tax, and for the period ended December 31, 2022, valuation allowances recorded on deferred tax assets. For the period ended December 31, 2021, there were also interest expense recognition differences for book and tax purposes.

Management assesses the available positive and negative evidence to estimate whether sufficient future taxable income will be generated to permit use of the existing deferred tax assets. A significant piece of objective negative evidence evaluated was the cumulative loss incurred in the U.S. over the three-year period ended December 31, 2022. Such objective evidence limits the ability to consider other subjective evidence, such as the Company’s projections for future income. On the basis of this evaluation, during the three months ended December 31, 2022, a valuation allowance of $6.1 million has been recorded to recognize only the portion of the U.S. deferred tax assets that is more likely than not to be realized. The amount of the deferred tax assets considered realizable, however, could be adjusted if estimates of future taxable income during the carryforward period are increased or reduced or if objective negative evidence in the form of cumulative losses is no longer present and additional weight is given to subjective evidence such as the Company’s projections for income.

As of December 31, 2022, and September 30, 2022, the Company had $87.2 million and $94.1 million, respectively of gross foreign federal NOL carryforwards that have no expiration date and $3.2 million at both December 31, 2022 and September 30, 2022 of net operating tax-effected state NOL carryforwards which expire beginning in 2035.

Canadian provincial tax authorities have challenged tax positions claimed by one of the Company’s Canadian subsidiaries and have issued tax reassessments for fiscal years 2002-2017. The reassessments are a result of ongoing audits and total $170.2 million, including interest, through December 31, 2022. The Company disputes these reassessments and will continue to work with the appropriate authorities in Canada to resolve the dispute. There is a reasonable possibility that the ultimate resolution of this dispute, and any related disputes for other open tax years, may be materially higher or lower than the amounts the Company has reserved for such disputes. In connection with this dispute, local regulations require the Company to post security with the tax authority until the dispute is resolved. The Company has posted collateral in the form of a $143.4 million performance bond and has paid $36.7 million to the Canadian tax authorities (most of which is recorded in other assets in the Consolidated Balance Sheets at December 31, 2022, and September 30, 2022), which is necessary to proceed with future appeals or litigation.
 
The Company expects that it will be required by local regulations to provide security for additional interest on the above unresolved disputed amounts and for any future reassessments issued by these Canadian tax authorities in the form of cash, letters of credit, performance bonds, asset liens or other arrangements agreeable with the tax authorities until the disputes are resolved.
The Company expects that the ultimate outcome of these matters will not have a material impact on its results of operations or financial condition. However, the Company can provide no assurance as to the ultimate outcome of these matters, and the impact could be material if they are not resolved in the Company’s favor. As of December 31, 2022, the Company believes it has adequately reserved for these reassessments.
 
Additionally, the Company has other uncertain tax positions as well as assessments and disputed positions with taxing authorities in its various jurisdictions, which are consistent with those matters disclosed in the Company’s Annual Report on Form 10-K for the annual period ended September 30, 2022.
v3.22.4
Long-Term Debt
 3 Months Ended
Dec. 31, 2022
Debt Disclosure [Abstract]  
Long-Term Debt Long-Term Debt:
 
Long-term debt consists of the following (in millions):
 December 31,
2022		September 30,
2022
4.875% Senior Notes due July 2024
$250.0 $250.0 
Term Loan due January 202516.9 16.9 
Revolving Credit Facility due January 2025— 151.5 
6.75% Senior Notes due December 2027
500.0 500.0 
AR Securitization Facility expires June 202572.9 37.5 
839.8 955.9 
Less unamortized debt issuance costs(7.7)(8.3)
Total debt832.1 947.6 
Less current portion— — 
Long-term debt$832.1 $947.6 

As of December 31, 2022, the term loan and revolving credit facility under the Company’s credit agreement entered into on November 26, 2019 (as amended, the “Credit Agreement”) were secured by substantially all existing and future U.S. assets of the Company, the Goderich mine in Ontario, Canada and capital stock of certain subsidiaries. As of December 31, 2022, the weighted average interest rate on all borrowings outstanding under the term loan under the Credit Agreement was approximately 6.4%.

The Company is in compliance as of December 31, 2022 with its debt covenants under the Credit Agreement and its AR Securitization Facility. Pursuant to the terms of the second amendment to the Credit Agreement the maximum allowed consolidated total net leverage ratio (as defined and calculated under the terms of the Credit Agreement and discussed further below) was 5.0x for the quarter ended December 31, 2022, which steps down to 4.75x in the quarter ending March 31, 2024, and to 4.5x for the fiscal quarter ended June 30, 2024 and thereafter. The consolidated total net leverage ratio represents the ratio of (a) consolidated total net debt to (b) consolidated adjusted earnings before interest, taxes, depreciation and amortization (“EBITDA”). Consolidated total net debt includes the aggregate principal amount of total debt, net of unrestricted cash not to exceed $50.0 million.

In November 2022, the Company entered into the third amendment to the 2019 Credit Agreement, principally to affect a transition from the London Inter-Bank Offered Rate to the Secured Overnight Financing Rate pricing benchmark provisions.

During the quarter ended December 31, 2022, the Company paid off the outstanding revolving credit facility balance utilizing proceeds from a private placement of common stock. Refer to Note 12 for additional details of the private placement transaction.

In January 2023, certain of the Company’s U.S. subsidiaries entered into the second amendment to the AR Securitization Facility with PNC Bank, which temporarily eases the restrictions of certain covenants contained in the agreement through March 2023. The amendment made certain adjustments to the financial tests including: (i) the default ratio and (ii) the delinquency ratio to make compliance with such tests more likely.
v3.22.4
Commitments and Contingencies
 3 Months Ended
Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]  
Commitments and Contingencies Commitments and Contingencies:
As previously disclosed, the Company was the subject of an investigation by the Division of Enforcement of the SEC regarding the Company’s disclosures primarily concerning the operation of the Goderich mine, the former South American businesses, and related accounting and internal control matters including Salt interim inventory valuation methodology issues that were disclosed in the Company’s Form 10-K/A for the year ended December 31, 2020, and Form 10-Q/A for the quarter ended March 31, 2021, each filed with the SEC on September 3, 2021.

On September 23, 2022, the Company reached a settlement with the SEC, concluding and resolving the SEC investigation in its entirety. Under the terms of the settlement, the Company, without admitting or denying the findings in the administrative order issued by the SEC, agreed to pay a civil penalty of $12 million and to cease and desist from violations of specified provisions of the federal securities laws and rules promulgated thereunder, and to retain an independent compliance consultant for a period of approximately one year to review certain accounting practices and procedures. As set forth in the administrative order, the $12 million civil penalty is to be paid in installments: $2 million, which was paid on September 29, 2022, and $10 million to be paid no later than September 30, 2023. The Company previously recorded an accrual for the full amount of the penalty in the third quarter of fiscal 2022, which is reflected in accrued expenses and other current liabilities on the Company’s Consolidated Balance Sheets.

The Company is also involved in legal and administrative proceedings and claims of various types from the ordinary course of the Company’s business.

Management cannot predict the outcome of legal claims and proceedings with certainty. Nevertheless, management believes that the outcome of legal proceeding and claims, which are pending or known to be threatened, even if determined adversely, will not, individually or in the aggregate, have a material adverse effect on the Company’s results of operations, cash flows or financial position, except as otherwise described in Note 8 and this Note 10.
v3.22.4
Operating Segments
 3 Months Ended
Dec. 31, 2022
Segment Reporting [Abstract]  
Operating Segments Operating Segments:
 
The Company’s reportable segments are strategic business units that offer different products and services, and each business requires different technology and marketing strategies. In connection with the executed business disposals discussed in Note 1 and Note 2, the Company has identified two reportable segments. The Specialty Businesses that comprised the Company’s former Plant Nutrition South America reportable segment and the North America micronutrient product business previously reported within the former Plant Nutrition North America reportable segment were classified as discontinued operations for all periods presented in its consolidated financial statements in this Quarterly Report on Form 10-Q.

For the three months ended December 31, 2022 and 2021, the Company has presented two reportable segments in its Consolidated Financial Statements: Salt and Plant Nutrition. The Salt segment produces and markets salt, consisting of sodium chloride and magnesium chloride, for use in road deicing for winter roadway safety and for dust control, food processing, water softening and other consumer, agricultural and industrial applications. The Plant Nutrition segment produces and markets various grades of SOP.

Segment information is as follows (in millions):
Three Months Ended December 31, 2022SaltPlant
Nutrition
Corporate
& Other(a)(b)
Total
Sales to external customers$308.1 $41.6 $2.7 $352.4 
Intersegment sales— 2.9 (2.9)— 
Shipping and handling cost102.7 4.7 — 107.4 
Operating earnings (loss)(b)
47.1 11.0 (30.2)27.9 
Depreciation, depletion and amortization13.9 8.3 1.7 23.9 
Total assets (as of end of period)985.2 456.5 323.0 1,764.7 
Three Months Ended December 31, 2021SaltPlant
Nutrition
Corporate
& Other(a)(b)
Total
Sales to external customers$273.9 $54.6 $3.0 $331.5 
Intersegment sales— 2.4 (2.4)— 
Shipping and handling cost88.4 7.3 — 95.7 
Operating earnings (loss)(b)
39.4 9.5 (28.5)20.4 
Depreciation, depletion and amortization16.2 8.8 3.3 28.3 
Total assets (as of end of period)1,035.4 445.3 206.7 1,687.4 

Disaggregated revenue by product type is as follows (in millions):
Three Months Ended December 31, 2022SaltPlant
Nutrition
Corporate
& Other(a)(b)
Total
Highway Deicing Salt$190.3 $— $— $190.3 
Consumer & Industrial Salt117.8 — — 117.8 
SOP— 44.5 — 44.5 
Eliminations & Other— (2.9)2.7 (0.2)
Sales to external customers$308.1 $41.6 $2.7 $352.4 

Three Months Ended December 31, 2021SaltPlant
Nutrition
Corporate
& Other(a)(b)
Total
Highway Deicing Salt$163.7 $— $— $163.7 
Consumer & Industrial Salt110.2 — — 110.2 
SOP— 57.0 — 57.0 
Eliminations & Other— (2.4)3.0 0.6 
Sales to external customers$273.9 $54.6 $3.0 $331.5 
(a)Corporate and Other includes corporate entities, records management operations, equity method investments, lithium development costs and other incidental operations and eliminations. Operating earnings (loss) for corporate and other includes indirect corporate overhead, including costs for general corporate governance and oversight, lithium-related expenses, as well as costs for the human resources, information technology, legal and finance functions.
(b)Corporate operating results include costs related to the settled SEC investigation of $0.3 million for the three months ended December 31, 2022. Corporate operating results for the three months ended December 31, 2021 include executive transition costs of $3.3 million and costs, net of reimbursements, related to the settled SEC investigation of $3.1 million. Refer to Note 10 for more information regarding the SEC investigation.

The Company’s revenue by geographic area is as follows (in millions):
Three Months Ended
December 31,
Revenue20222021
United States(a)
$248.2 $221.3 
Canada87.6 89.4 
United Kingdom14.1 19.8 
Other2.5 1.0 
Total revenue$352.4 $331.5 
(a)United States sales exclude product sold to foreign customers at U.S. ports.
v3.22.4
Stockholders' Equity and Equity Instruments
 3 Months Ended
Dec. 31, 2022
Equity [Abstract]  
Stockholders' Equity and Equity Instruments Stockholders’ Equity and Equity Instruments:
In May 2020, the Company’s stockholders approved the 2020 Incentive Award Plan (as amended, the “2020 Plan”), which authorized the issuance of 2,977,933 shares of Company common stock. In February 2022, the Company’s stockholders approved an amendment to the 2020 Plan authorizing an additional 750,000 shares of Company stock. Since the date the 2020 Plan was approved, the Company ceased issuing equity awards under the 2015 Incentive Award Plan (as amended, the “2015 Plan”). Since the approval of the 2015 Plan in May 2015, the Company ceased issuing equity awards under the 2005 Incentive Award Plan (as amended, the “2005 Plan”). The 2005 Plan, the 2015 Plan and the 2020 Plan allow for grants of equity awards to executive officers, other employees and directors, including restricted stock units (“RSUs”), performance stock units (“PSUs”), stock options and deferred stock units.

Koch Equity Investment

On September 14, 2022, the Company entered into a Stock Purchase Agreement with Koch Minerals & Trading, LLC (“KM&T”), a subsidiary of Koch Industries, Inc. (“KII”), pursuant to which the Company agreed to issue and sell 6,830,700 shares of its common stock at a purchase price of $36.87 for aggregate net proceeds of approximately $240.7 million, net of transaction costs. On October 18, 2022, the Company closed the direct private placement with KM&T, through its affiliate KM&T Investment Holdings, LLC, resulting in their ownership of approximately 17% of the Company’s outstanding common stock. The Company expects to use approximately $200 million of the proceeds from the private placement to advance the first development phase of its sustainable lithium development project at its Ogden site. The Company used the remaining approximately $40.7 million of proceeds to reduce debt.

Options

Substantially all of the stock options granted vest ratably, in tranches, over a four-year service period. Unexercised options expire after seven years. Options do not have dividend or voting rights. Upon vesting, each option can be exercised to purchase one share of the Company’s common stock. The exercise price of options is equal to the closing stock price on the grant date.

To estimate the fair value of options on the grant date, the Company uses the Black-Scholes option valuation model. Award recipients are grouped according to expected exercise behavior. Unless better information is available to estimate the expected term of the options, the estimate is based on historical exercise experience. The risk-free rate, using U.S. Treasury yield curves in effect at the time of grant, is selected based on the expected term of each group. The Company’s historical stock price is used to estimate expected volatility.

RSUs

Typically, the RSUs granted under the 2015 Plan and the 2020 Plan vest after one to three years of service. RSUs entitle the holders to one share of common stock for each vested RSU. Unvested RSUs do not have voting rights but are entitled to receive non-forfeitable dividends (generally after a performance hurdle has been satisfied for the year of the grant) or other distributions equal to those declared on the Company’s common stock for RSUs that are earned as a result of the satisfaction of the performance hurdle. The closing stock price on the grant date is used to determine the fair value of RSUs.

PSUs

Substantially all of the PSUs outstanding under the 2015 Plan and the 2020 Plan are either total stockholder return PSUs (“TSR PSUs”) or adjusted EBITDA growth PSUs (“EBITDA Growth PSUs”). The actual number of shares of the Company’s common stock that may be earned with respect to TSR PSUs is calculated by comparing the Company’s total stockholder return to the total stockholder return for each company comprising the Company’s peer group or a total return percentage target over a two- or three-year performance period and may range from 0% to 300% of the target number of shares based upon the attainment of these performance conditions. The actual number of shares of common stock that may be earned with respect to EBITDA Growth PSUs is calculated based on the attainment of adjusted EBITDA growth during the performance period and may range from 0% to 300% of the target number of shares based upon the attainment of these performance conditions.

PSUs represent a target number of shares of the Company’s common stock that may be earned before adjustment based upon the attainment of certain performance conditions. Holders of PSUs do not have voting rights but are entitled to receive non-forfeitable dividends or other distributions equal to those declared on the Company’s common stock for PSUs that are earned, which are paid when the shares underlying the PSUs are issued.
To estimate the fair value of the TSR PSUs on the grant date for accounting purposes, the Company uses a Monte-Carlo simulation model, which simulates future stock prices of the Company as well as the Company’s peer group. This model uses historical stock prices to estimate expected volatility and the Company’s correlation to the peer group. The risk-free rate was determined using the same methodology as the option valuations as discussed above. The Company’s closing stock price on the grant date was used to estimate the fair value of the EBITDA Growth PSUs. The Company will adjust the expense of the EBITDA Growth PSUs based upon its estimate of the number of shares that will ultimately vest at each interim date during the vesting period.

During the three months ended December 31, 2022, the Company reissued the following number of shares from treasury stock: 31,140 shares related to the release of RSUs which vested and 936 shares related to stock payments. In fiscal 2022, the Company issued 117,390 net shares from treasury stock. The Company withheld a total of 9,853 shares with a fair value of $0.4 million related to the vesting of RSUs, PSUs, and stock payments during the three months ended December 31, 2022. The fair value of the shares were valued at the closing price at the vesting date and represent the employee tax withholding for the employee’s compensation. The Company recognized tax expense of $0.1 million from its equity compensation awards as an increase to income tax expense during the three months ended December 31, 2022. During the three months ended December 31, 2022 and 2021, the Company recorded $10.6 million and $4.7 million (includes $1.4 million paid in cash), respectively, of compensation expense pursuant to its stock-based compensation plans. No amounts have been capitalized. The following table summarizes stock-based compensation activity during the three months ended December 31, 2022:
 Stock OptionsRSUs
PSUs(a)
 NumberWeighted-average
exercise price		NumberWeighted-average
fair value		NumberWeighted-average
fair value
Outstanding at September 30, 2022
774,580 $60.68 208,735 $63.02 331,359 $71.51 
Granted— — 221,151 38.14 182,422 68.29 
Exercised(b)
— — — — — — 
Released from restriction(b)
— — (31,755)67.61 — — 
Cancelled/expired(13,241)62.57 (4,496)46.27 — — 
Outstanding at December 31, 2022
761,339 $60.64 393,635 $48.86 513,781 $70.37 
(a)Until the performance period is completed, PSUs are included in the table at the target level at their grant date and at that level represent one share of common stock per PSU.
(b)Common stock issued for exercised options and for vested and earned RSUs and PSUs was issued from treasury stock.

Accumulated Other Comprehensive Loss (“AOCL”)

The Company’s comprehensive income (loss) is comprised of net earnings (loss), net amortization of the unrealized loss of the pension obligation, the change in the unrealized gain in other postretirement benefits, the change in the unrealized gain (loss) on natural gas and foreign currency cash flow hedges and CTA. The components of and changes in AOCL are as follows (in millions):
Three Months Ended December 31, 2022(a)
Losses on Cash Flow HedgesDefined Benefit PensionOther Post-Employment BenefitsForeign
Currency		Total
Beginning balance$(1.6)$(2.7)$1.3 $(112.3)$(115.3)
Other comprehensive (loss) income before reclassifications(b)
(2.4)— — 11.7 9.3 
Amounts reclassified from AOCL(0.4)0.1 — — (0.3)
Net current period other comprehensive (loss) income(2.8)0.1 — 11.7 9.0 
Ending balance$(4.4)$(2.6)$1.3 $(100.6)$(106.3)
Three Months Ended December 31, 2021(a)
Gains and (Losses) on Cash Flow HedgesDefined Benefit PensionForeign
Currency		Total
Beginning balance$3.1 $(5.4)$(108.2)$(110.5)
Other comprehensive loss before reclassifications(b)
(0.9)— (3.8)(4.7)
Amounts reclassified from AOCL(1.1)0.1 — (1.0)
Net current period other comprehensive (loss) income(2.0)0.1 (3.8)(5.7)
Ending balance$1.1 $(5.3)$(112.0)$(116.2)
(a)With the exception of the CTA, for which no tax effect is recorded, the changes in the components of AOCL presented in the tables above are reflected net of applicable income taxes.
(b)The Company recorded foreign exchange (loss) gain of $(1.3) million in the three months ended December 31, 2022, and $1.2 million in the three months ended December 31, 2021, in AOCL related to intercompany notes which were deemed to be of a long-term investment nature.

The amounts reclassified from AOCL to expense (income) for the three months ended December 31, 2022 and 2021, are shown below (in millions):
Amount Reclassified from AOCL
 Three Months Ended
December 31,		Line Item Impacted in the
Consolidated Statements of Operations
20222021
Losses on cash flow hedges:
Natural gas instruments$(0.5)$(1.5)Product cost
Income tax expense0.1 0.4 
Reclassifications, net of income taxes(0.4)(1.1)
Amortization of defined benefit pension: 
Amortization of loss0.1 0.1 Product cost
Income tax benefit— — 
Reclassifications, net of income taxes0.1 0.1  
Amortization of other post-employment benefits:
Amortization of loss— — Product cost
Income tax benefit— — 
Reclassifications, net of income taxes— — 
Total reclassifications, net of income taxes$(0.3)$(1.0) 
v3.22.4
Derivative Financial Instruments
 3 Months Ended
Dec. 31, 2022
Derivative Instruments and Hedging Activities Disclosure [Abstract]  
Derivative Financial Instruments Derivative Financial Instruments:
 
The Company is subject to various types of market risks, including interest rate risk, foreign currency exchange rate transaction and translation risk and commodity pricing risk. Management may take actions to mitigate the exposure to these types of risks, including entering into forward purchase contracts and other financial instruments. The Company manages a portion of its commodity pricing risks and foreign currency exchange rate risks by using derivative instruments. From time to time, the Company may enter into foreign exchange contracts to mitigate foreign exchange risk. The Company does not seek to engage in trading activities or take speculative positions with any financial instrument arrangement. The Company has entered into natural gas derivative instruments and foreign currency derivative instruments with counterparties it views as creditworthy. However, the Company does attempt to mitigate its counterparty credit risk exposures by, among other things, entering into master netting agreements with some of these counterparties. The Company records derivative financial instruments as either assets or liabilities at fair value in its Consolidated Balance Sheets. The assets and liabilities recorded as of December 31, 2022 and September 30, 2022 were not material.

Derivatives qualify for treatment as hedges when there is a high correlation between the change in fair value of the derivative instrument and the related change in value of the underlying hedged item. Depending on the exposure being hedged, the Company must designate the hedging instrument as a fair value hedge, a cash flow hedge or a net investment in foreign operations hedge. For the qualifying derivative instruments that have been designated as hedges, the effective portion of the change in fair value is recognized through earnings when the underlying transaction being hedged affects earnings, allowing a derivative’s gains and losses to offset related results from the hedged item in the Consolidated Statements of Operations. Any
ineffectiveness related to these hedges was not material for any of the periods presented. For derivative instruments that have not been designated as hedges, the entire change in fair value is recorded through earnings in the period of change.

Natural Gas Derivative Instruments

Natural gas is consumed at several of the Company’s production facilities, and changes in natural gas prices impact the Company’s operating margin. The Company seeks to reduce the earnings and cash flow impacts of changes in market prices of natural gas by fixing the purchase price of up to 90% of its forecasted natural gas usage. It is the Company’s policy to consider hedging portions of its natural gas usage up to 36 months in advance of the forecasted purchase. As of December 31, 2022, the Company had entered into natural gas derivative instruments to hedge a portion of its natural gas purchase requirements through September 2024. As of December 31, 2022 and September 30, 2022, the Company had agreements in place to hedge forecasted natural gas purchases of 3.1 million and 3.8 million MMBtus, respectively. All natural gas derivative instruments held by the Company as of December 31, 2022 and September 30, 2022 qualified and were designated as cash flow hedges. As of December 31, 2022, the Company expects to reclassify from AOCL to earnings during the next twelve months $3.7 million of net losses on derivative instruments related to its natural gas hedges. Refer to Note 14 for the estimated fair value of the Company’s natural gas derivative instruments as of December 31, 2022 and September 30, 2022.

The following tables present the fair value of the Company’s derivatives (in millions):
 Asset DerivativesLiability Derivatives
Derivatives designated as hedging instruments:Consolidated Balance Sheet LocationDecember 31, 2022Consolidated Balance Sheet LocationDecember 31, 2022
Commodity contractsOther current assets$1.6 Accrued expenses and other current liabilities$5.2 
Commodity contractsOther assets0.1 Other noncurrent liabilities0.8 
Total derivatives designated as hedging instruments(a)
$1.7 $6.0 
(a)The Company has master netting agreements with its commodity hedge counterparties and accordingly has netted in its Consolidated Balance Sheets $1.7 million of its commodity contracts that are in receivable positions against its contracts in payable positions.

 Asset DerivativesLiability Derivatives
Derivatives designated as hedging instruments:Consolidated Balance Sheet LocationSeptember 30, 2022Consolidated Balance Sheet LocationSeptember 30, 2022
Commodity contractsOther current assets$2.7 Accrued expenses and other current liabilities$3.3 
Commodity contractsOther assets0.2 Other noncurrent liabilities0.7 
Total derivatives designated as hedging instruments(a)
$2.9 $4.0 
(a)The Company has master netting agreements with its commodity hedge counterparties and accordingly has netted in its Consolidated Balance Sheets $2.9 million of its commodity contracts that are in receivable positions against its contracts in payable positions.
v3.22.4
Fair Value Measurements
 3 Months Ended
Dec. 31, 2022
Fair Value Disclosures [Abstract]  
Fair Value Measurements Fair Value Measurements:
The Company’s financial instruments are measured and reported at their estimated fair values. Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction. When available, the Company uses quoted prices in active markets to determine the fair values for its financial instruments (Level 1 inputs) or, absent quoted market prices, observable market-corroborated inputs over the term of the financial instruments (Level 2 inputs). The Company does not have any unobservable inputs that are not corroborated by market inputs (Level 3 inputs).
 
The Company holds marketable securities associated with its defined contribution and pre-tax savings plans, which are valued based on readily available quoted market prices. The Company utilizes derivative instruments to manage its risk of changes in natural gas prices and foreign exchange rates (see Note 13). The fair values of the natural gas and foreign currency derivative instruments are determined using market data of forward prices for all of the Company’s contracts. 
The estimated fair values for each type of instrument are presented below (in millions):
 December 31,
2022		Level OneLevel TwoLevel Three
Asset Class:
Mutual fund investments in a non-qualified savings plan(a)
$2.5 $2.5 $— $— 
Total Assets$2.5 $2.5 $— $— 
Liability Class:    
Derivatives - natural gas instruments, net$(4.3)$— $(4.3)$— 
Liabilities related to non-qualified savings plan(2.5)(2.5)— — 
Total Liabilities$(6.8)$(2.5)$(4.3)$— 
(a)Includes mutual fund investments of approximately 25% in common stock of large-cap U.S. companies, 5% in common stock of small to mid-cap U.S. companies, 10% in international companies, 15% in bond funds, 5% in short-term investments and 40% in blended funds.

 September 30,
2022		 
Level One		 
Level Two		 
Level Three
Asset Class:
Mutual fund investments in a non-qualified savings plan(a)
$1.8 $1.8 $— $— 
Total Assets$1.8 $1.8 $— $— 
Liability Class:    
Derivatives – natural gas instruments, net$(1.1)$— $(1.1)$— 
Liabilities related to non-qualified savings plan(1.8)(1.8)— — 
Total Liabilities$(2.9)$(1.8)$(1.1)$— 
(a)Includes mutual fund investments of approximately 30% in the common stock of large-cap U.S. companies, 5% in the common stock of small to mid-cap U.S. companies, 10% in the common stock of international companies, 15% in bond funds, 5% in short-term investments and 35% in blended funds.
Cash and cash equivalents, receivables (net of allowance for doubtful accounts) and accounts payable are carried at cost, which approximates fair value due to their liquid and short-term nature. The Company’s investments related to its nonqualified retirement plan of $2.5 million at December 31, 2022 and $1.8 million at September 30, 2022, are stated at fair value based on quoted market prices. As of December 31, 2022 and September 30, 2022, the estimated fair value of the Company’s fixed-rate 4.875% Senior Notes due July 2024, based on available trading information (Level 2), totaled $239.9 million and $235.9 million, respectively, compared with the aggregate principal amount at maturity of $250.0 million. As of December 31, 2022 and September 30, 2022, the estimated fair value of the Company’s fixed-rate 6.75% Senior Notes due December 2027, based on available trading information (Level 2), totaled $479.4 million and $468.9 million, respectively, compared with the aggregate principal amount at maturity of $500.0 million. The fair value at December 31, 2022 and September 30, 2022 of amounts outstanding under the Company’s term loans and revolving credit facility, based upon available bid information received from the Company’s lender (Level 2), totaled approximately $16.8 million and $158.5 million, respectively, compared with the aggregate principal amount at maturity of $16.9 million and $168.4 million, respectively.
v3.22.4
Earnings per Share
 3 Months Ended
Dec. 31, 2022
Earnings Per Share [Abstract]  
Earnings per Share Earnings per Share:
 
The Company calculates earnings per share using the two-class method. The two-class method requires allocating the Company’s net earnings to both common shares and participating securities. The following table sets forth the computation of basic and diluted earnings per common share (in millions, except for share and per-share data):
 Three Months Ended
December 31,
 20222021
Numerator:
Net (loss) earnings from continuing operations$(0.3)$7.9 
Less: net earnings allocated to participating securities(a)
(0.1)(0.1)
Net (loss) earnings from continuing operations available to common stockholders(0.4)7.8 
Net loss from discontinued operations available to common stockholders— (5.5)
Net (loss) earnings available to common stockholders$(0.4)$2.3 
Denominator (in thousands):
Weighted-average common shares outstanding, shares for basic earnings per share39,751 34,060 
Weighted-average awards outstanding(b)
— 29 
Shares for diluted earnings per share39,751 34,089 
Basic net (loss) earnings from continuing operations per common share$(0.01)$0.23 
Basic net loss from discontinued operations per common share— (0.16)
Basic net (loss) earnings per common share$(0.01)$0.07 
Diluted net (loss) earnings from continuing operations per common share$(0.01)$0.23 
Diluted net loss from discontinued operations per common share— (0.16)
Diluted net (loss) earnings per common share$(0.01)$0.07 
(a)Weighted participating securities include RSUs and PSUs that receive non-forfeitable dividends and consist of 514,000 weighted participating securities for the three months ended December 31, 2022, and 430,000 weighted participating securities for the three months ended December 31, 2021.
(b)For the calculation of diluted net earnings per share, the Company uses the more dilutive of either the treasury stock method or the two-class method to determine the weighted-average number of outstanding common shares. In addition, the Company had 1,272,000 weighted-average equity awards outstanding for the three months ended December 31, 2022, and 1,097,000 weighted-average equity awards outstanding for the three months ended December 31, 2021, that were anti-dilutive.
v3.22.4
Related Party Transactions
 3 Months Ended
Dec. 31, 2022
Related Party Transactions [Abstract]  
Related Party Transactions Related Party Transactions:
As discussed in Note 12, on October 18, 2022, KII, through its KM&T subsidiary, purchased common stock representing an ownership interest of approximately 17% of the outstanding common stock of the Company. As part of the Stock Purchase Agreement, KM&T appointed two members to the Company’s board of directors, effective November 13, 2022. In addition, the companies are currently exploring value creation opportunities by leveraging the capabilities of select KII operating subsidiaries.

During the three months ended December 31, 2022 and 2021, the Company recorded SOP sales of approximately $0.9 million and $0.7 million, respectively, to certain subsidiaries of KII. As of December 31, 2022 and September 30, 2022, the Company had approximately $0.5 million and $0.4 million, respectively, of Receivables from related parties on its Consolidated Balance Sheets. Additionally, the Company has recently engaged a subsidiary of KII to provide engineering services for the Company’s lithium development project for which it capitalized approximately $0.5 million into Property, Plant and Equipment, net during the quarter ended December 31, 2022 of which $0.3 million was included in Accounts Payable as of December 31, 2022.
On December 20, 2022, the Company paid a cash dividend to its stockholders of record at the close of business on December 9, 2022 in the amount of $0.15 per share, or $6.3 million in the aggregate. KM&T received approximately $1.0 million in respect to its common shares.
v3.22.4
Accounting Policies and Basis of Presentation (Policies)
 3 Months Ended
Dec. 31, 2022
Accounting Policies [Abstract]  
Basis of Consolidation CMI is a holding company with no significant operations other than those of its wholly-owned subsidiaries. The consolidated financial statements include the accounts of CMI and its wholly-owned domestic and foreign subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation.
Basis of Presentation The accompanying unaudited consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete consolidated financial statements. These unaudited consolidated financial statements should be read in conjunction with the consolidated financial statements of the Company for the annual period ended September 30, 2022, as filed with the Securities and Exchange Commission (the “SEC”) in its Annual Report on Form 10-K on December 14, 2022. In the opinion of management, all adjustments, consisting of normal recurring adjustments considered necessary for a fair presentation, have been included.
Significant and Recent Accounting Pronouncements
Significant Accounting Policies

The Company’s significant accounting policies are detailed in “Note 2 – Summary of Significant Accounting Policies” within Part II, Item 8 of its Annual Report on Form 10-K for the annual period ended September 30, 2022. The Company reports its financial results from discontinued operations and continuing operations separately to recognize the financial impact of disposal transactions apart from ongoing operations. Discontinued operations reporting occurs when a component or a group of components of an entity has been disposed or classified as held for sale and represents a strategic shift that has a major effect on the entity’s operations and financial results. In the Company’s Consolidated Statements of Cash Flows, the cash flows from discontinued operations are not separately classified. Unless otherwise indicated, amounts provided in these Notes pertain to continuing operations. See Note 2 for information on discontinued operations and Note 11 for information on the Company’s reportable segments.
Recent Accounting Pronouncements

The Company has evaluated all of the recently issued, but not yet effective, accounting standards that have been issued or proposed by the Financial Accounting Standards Board or other standards-setting bodies through the filing date of these unaudited consolidated financial statements and does not believe the future adoption of any such pronouncements will have a material impact on its consolidated financial statements.
Strategic Evaluation and Plan to Sell Businesses
Strategic Evaluation and Plan to Sell Businesses

Following an evaluation of the strategic fit of certain of the Company’s businesses and subsequent restructuring of its former South American Plant Nutrition segment to enable separate sales processes for its chemicals and specialty plant nutrition businesses and equity investment in Fermavi Eletroquímica Ltda. (“Fermavi”), in fiscal 2021 the Company’s Board of Directors approved the plan to sell each of these businesses and the North America micronutrient business (the “Specialty Businesses”) with a goal of reducing the Company’s leverage and enabling increased focus on optimizing the Company’s core businesses.

The Company concluded that the sale of the Specialty Businesses represented a strategic shift for the Company that would have a material effect on its operations and financial results. Consequently, the Specialty businesses were reclassified as discontinued operations on the Consolidated Statements of Operations. See Note 2 for further discussion of the sales of these businesses.
Unless otherwise indicated, amounts provided in these Notes pertain to continuing operations.
Derivative Financial Instruments
The Company is subject to various types of market risks, including interest rate risk, foreign currency exchange rate transaction and translation risk and commodity pricing risk. Management may take actions to mitigate the exposure to these types of risks, including entering into forward purchase contracts and other financial instruments. The Company manages a portion of its commodity pricing risks and foreign currency exchange rate risks by using derivative instruments. From time to time, the Company may enter into foreign exchange contracts to mitigate foreign exchange risk. The Company does not seek to engage in trading activities or take speculative positions with any financial instrument arrangement. The Company has entered into natural gas derivative instruments and foreign currency derivative instruments with counterparties it views as creditworthy. However, the Company does attempt to mitigate its counterparty credit risk exposures by, among other things, entering into master netting agreements with some of these counterparties. The Company records derivative financial instruments as either assets or liabilities at fair value in its Consolidated Balance Sheets. The assets and liabilities recorded as of December 31, 2022 and September 30, 2022 were not material.

Derivatives qualify for treatment as hedges when there is a high correlation between the change in fair value of the derivative instrument and the related change in value of the underlying hedged item. Depending on the exposure being hedged, the Company must designate the hedging instrument as a fair value hedge, a cash flow hedge or a net investment in foreign operations hedge. For the qualifying derivative instruments that have been designated as hedges, the effective portion of the change in fair value is recognized through earnings when the underlying transaction being hedged affects earnings, allowing a derivative’s gains and losses to offset related results from the hedged item in the Consolidated Statements of Operations. Any
ineffectiveness related to these hedges was not material for any of the periods presented. For derivative instruments that have not been designated as hedges, the entire change in fair value is recorded through earnings in the period of change.
Earnings Per Share The Company calculates earnings per share using the two-class method. The two-class method requires allocating the Company’s net earnings to both common shares and participating securities.
v3.22.4
Discontinued Operations (Tables)
 3 Months Ended
Dec. 31, 2022
Discontinued Operations and Disposal Groups [Abstract]  
Disposal Groups, Including Discontinued Operations
The following table represents summarized Consolidated Statements of Operations information of discontinued operations (in millions):

Three Months Ended
December 31,
2021
Sales$22.4 
Shipping and handling cost1.2 
Product cost10.9 
Gross profit10.3 
Selling, general and administrative expenses1.6 
Operating earnings8.7 
Loss on foreign exchange3.1 
Net loss on adjustment to fair value less estimated costs to sell8.4 
Other income, net(0.2)
Loss from discontinued operations before income taxes(2.6)
Income tax expense2.9 
Net loss from discontinued operations$(5.5)

The significant components included in the Company’s Consolidated Statements of Cash Flows for discontinued operations are as follows (in millions):

Three Months Ended
December 31,
2021
Loss on impairment of long-lived assets$8.4 
Capital expenditures(0.7)
v3.22.4
Inventories (Tables)
 3 Months Ended
Dec. 31, 2022
Inventory Disclosure [Abstract]  
Summary of Inventories
Inventories consist of the following (in millions):
 December 31,
2022		September 30,
2022
Finished goods$242.3 $251.6 
Raw materials and supplies58.7 52.8 
Total inventories$301.0 $304.4 
v3.22.4
Property, Plant and Equipment, Net (Tables)
 3 Months Ended
Dec. 31, 2022
Property, Plant and Equipment [Abstract]  
Summary of Property, Plant and Equipment, Net
Property, plant and equipment, net, consists of the following (in millions):
 December 31,
2022		September 30,
2022
Land, buildings and structures, and leasehold improvements$543.0 $534.8 
Machinery and equipment1,058.2 1,026.3 
Office furniture and equipment56.9 56.8 
Mineral interests168.7 167.1 
Construction in progress48.0 64.3 
 1,874.8 1,849.3 
Less: accumulated depreciation and depletion(1,100.0)(1,072.7)
Property, plant and equipment, net$774.8 $776.6 
v3.22.4
Goodwill and Intangible Assets, Net (Tables)
 3 Months Ended
Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]  
Summary of Intangible Assets
Amounts related to the Company’s amortization of intangible assets are as follows (in millions):
Three Months Ended
December 31,
20222021
Aggregate amortization expense$0.4 $0.4 
Summary of Goodwill
Amounts related to the Company’s goodwill are as follows (in millions):
December 31,
2022		September 30,
2022
Plant Nutrition$51.0 $50.9 
Other5.8 5.5 
Total$56.8 $56.4 
v3.22.4
Long-Term Debt (Tables)
 3 Months Ended
Dec. 31, 2022
Debt Disclosure [Abstract]  
Summary of Long-Term Debt
Long-term debt consists of the following (in millions):
 December 31,
2022		September 30,
2022
4.875% Senior Notes due July 2024
$250.0 $250.0 
Term Loan due January 202516.9 16.9 
Revolving Credit Facility due January 2025— 151.5 
6.75% Senior Notes due December 2027
500.0 500.0 
AR Securitization Facility expires June 202572.9 37.5 
839.8 955.9 
Less unamortized debt issuance costs(7.7)(8.3)
Total debt832.1 947.6 
Less current portion— — 
Long-term debt$832.1 $947.6 
v3.22.4
Operating Segments (Tables)
 3 Months Ended
Dec. 31, 2022
Segment Reporting [Abstract]  
Summary of Segment Information
Segment information is as follows (in millions):
Three Months Ended December 31, 2022SaltPlant
Nutrition
Corporate
& Other(a)(b)
Total
Sales to external customers$308.1 $41.6 $2.7 $352.4 
Intersegment sales— 2.9 (2.9)— 
Shipping and handling cost102.7 4.7 — 107.4 
Operating earnings (loss)(b)
47.1 11.0 (30.2)27.9 
Depreciation, depletion and amortization13.9 8.3 1.7 23.9 
Total assets (as of end of period)985.2 456.5 323.0 1,764.7 
Three Months Ended December 31, 2021SaltPlant
Nutrition
Corporate
& Other(a)(b)
Total
Sales to external customers$273.9 $54.6 $3.0 $331.5 
Intersegment sales— 2.4 (2.4)— 
Shipping and handling cost88.4 7.3 — 95.7 
Operating earnings (loss)(b)
39.4 9.5 (28.5)20.4 
Depreciation, depletion and amortization16.2 8.8 3.3 28.3 
Total assets (as of end of period)1,035.4 445.3 206.7 1,687.4 
Summary of Disaggregated Revenue by Product Type
Disaggregated revenue by product type is as follows (in millions):
Three Months Ended December 31, 2022SaltPlant
Nutrition
Corporate
& Other(a)(b)
Total
Highway Deicing Salt$190.3 $— $— $190.3 
Consumer & Industrial Salt117.8 — — 117.8 
SOP— 44.5 — 44.5 
Eliminations & Other— (2.9)2.7 (0.2)
Sales to external customers$308.1 $41.6 $2.7 $352.4 

Three Months Ended December 31, 2021SaltPlant
Nutrition
Corporate
& Other(a)(b)
Total
Highway Deicing Salt$163.7 $— $— $163.7 
Consumer & Industrial Salt110.2 — — 110.2 
SOP— 57.0 — 57.0 
Eliminations & Other— (2.4)3.0 0.6 
Sales to external customers$273.9 $54.6 $3.0 $331.5 
(a)Corporate and Other includes corporate entities, records management operations, equity method investments, lithium development costs and other incidental operations and eliminations. Operating earnings (loss) for corporate and other includes indirect corporate overhead, including costs for general corporate governance and oversight, lithium-related expenses, as well as costs for the human resources, information technology, legal and finance functions.
(b)Corporate operating results include costs related to the settled SEC investigation of $0.3 million for the three months ended December 31, 2022. Corporate operating results for the three months ended December 31, 2021 include executive transition costs of $3.3 million and costs, net of reimbursements, related to the settled SEC investigation of $3.1 million. Refer to Note 10 for more information regarding the SEC investigation.
Summary of Revenue by Geographic Area
The Company’s revenue by geographic area is as follows (in millions):
Three Months Ended
December 31,
Revenue20222021
United States(a)
$248.2 $221.3 
Canada87.6 89.4 
United Kingdom14.1 19.8 
Other2.5 1.0 
Total revenue$352.4 $331.5 
(a)United States sales exclude product sold to foreign customers at U.S. ports.
v3.22.4
Stockholders' Equity and Equity Instruments (Tables)
 3 Months Ended
Dec. 31, 2022
Equity [Abstract]  
Summary of Stock-Based Compensation Activity The following table summarizes stock-based compensation activity during the three months ended December 31, 2022:
 Stock OptionsRSUs
PSUs(a)
 NumberWeighted-average
exercise price		NumberWeighted-average
fair value		NumberWeighted-average
fair value
Outstanding at September 30, 2022
774,580 $60.68 208,735 $63.02 331,359 $71.51 
Granted— — 221,151 38.14 182,422 68.29 
Exercised(b)
— — — — — — 
Released from restriction(b)
— — (31,755)67.61 — — 
Cancelled/expired(13,241)62.57 (4,496)46.27 — — 
Outstanding at December 31, 2022
761,339 $60.64 393,635 $48.86 513,781 $70.37 
(a)Until the performance period is completed, PSUs are included in the table at the target level at their grant date and at that level represent one share of common stock per PSU.
(b)Common stock issued for exercised options and for vested and earned RSUs and PSUs was issued from treasury stock.
Summary of Components and Changes in Accumulated Other Comprehensive Income (Loss) The components of and changes in AOCL are as follows (in millions):
Three Months Ended December 31, 2022(a)
Losses on Cash Flow HedgesDefined Benefit PensionOther Post-Employment BenefitsForeign
Currency		Total
Beginning balance$(1.6)$(2.7)$1.3 $(112.3)$(115.3)
Other comprehensive (loss) income before reclassifications(b)
(2.4)— — 11.7 9.3 
Amounts reclassified from AOCL(0.4)0.1 — — (0.3)
Net current period other comprehensive (loss) income(2.8)0.1 — 11.7 9.0 
Ending balance$(4.4)$(2.6)$1.3 $(100.6)$(106.3)
Three Months Ended December 31, 2021(a)
Gains and (Losses) on Cash Flow HedgesDefined Benefit PensionForeign
Currency		Total
Beginning balance$3.1 $(5.4)$(108.2)$(110.5)
Other comprehensive loss before reclassifications(b)
(0.9)— (3.8)(4.7)
Amounts reclassified from AOCL(1.1)0.1 — (1.0)
Net current period other comprehensive (loss) income(2.0)0.1 (3.8)(5.7)
Ending balance$1.1 $(5.3)$(112.0)$(116.2)
(a)With the exception of the CTA, for which no tax effect is recorded, the changes in the components of AOCL presented in the tables above are reflected net of applicable income taxes.
(b)The Company recorded foreign exchange (loss) gain of $(1.3) million in the three months ended December 31, 2022, and $1.2 million in the three months ended December 31, 2021, in AOCL related to intercompany notes which were deemed to be of a long-term investment nature.
Summary of Reclassifications out of Accumulated Other Comprehensive Income
The amounts reclassified from AOCL to expense (income) for the three months ended December 31, 2022 and 2021, are shown below (in millions):
Amount Reclassified from AOCL
 Three Months Ended
December 31,		Line Item Impacted in the
Consolidated Statements of Operations
20222021
Losses on cash flow hedges:
Natural gas instruments$(0.5)$(1.5)Product cost
Income tax expense0.1 0.4 
Reclassifications, net of income taxes(0.4)(1.1)
Amortization of defined benefit pension: 
Amortization of loss0.1 0.1 Product cost
Income tax benefit— — 
Reclassifications, net of income taxes0.1 0.1  
Amortization of other post-employment benefits:
Amortization of loss— — Product cost
Income tax benefit— — 
Reclassifications, net of income taxes— — 
Total reclassifications, net of income taxes$(0.3)$(1.0) 
v3.22.4
Derivative Financial Instruments (Tables)
 3 Months Ended
Dec. 31, 2022
Derivative Instruments and Hedging Activities Disclosure [Abstract]  
Summary of Fair Value of Hedges
The following tables present the fair value of the Company’s derivatives (in millions):
 Asset DerivativesLiability Derivatives
Derivatives designated as hedging instruments:Consolidated Balance Sheet LocationDecember 31, 2022Consolidated Balance Sheet LocationDecember 31, 2022
Commodity contractsOther current assets$1.6 Accrued expenses and other current liabilities$5.2 
Commodity contractsOther assets0.1 Other noncurrent liabilities0.8 
Total derivatives designated as hedging instruments(a)
$1.7 $6.0 
(a)The Company has master netting agreements with its commodity hedge counterparties and accordingly has netted in its Consolidated Balance Sheets $1.7 million of its commodity contracts that are in receivable positions against its contracts in payable positions.

 Asset DerivativesLiability Derivatives
Derivatives designated as hedging instruments:Consolidated Balance Sheet LocationSeptember 30, 2022Consolidated Balance Sheet LocationSeptember 30, 2022
Commodity contractsOther current assets$2.7 Accrued expenses and other current liabilities$3.3 
Commodity contractsOther assets0.2 Other noncurrent liabilities0.7 
Total derivatives designated as hedging instruments(a)
$2.9 $4.0 
(a)The Company has master netting agreements with its commodity hedge counterparties and accordingly has netted in its Consolidated Balance Sheets $2.9 million of its commodity contracts that are in receivable positions against its contracts in payable positions.
v3.22.4
Fair Value Measurements (Tables)
 3 Months Ended
Dec. 31, 2022
Fair Value Disclosures [Abstract]  
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis
The estimated fair values for each type of instrument are presented below (in millions):
 December 31,
2022		Level OneLevel TwoLevel Three
Asset Class:
Mutual fund investments in a non-qualified savings plan(a)
$2.5 $2.5 $— $— 
Total Assets$2.5 $2.5 $— $— 
Liability Class:    
Derivatives - natural gas instruments, net$(4.3)$— $(4.3)$— 
Liabilities related to non-qualified savings plan(2.5)(2.5)— — 
Total Liabilities$(6.8)$(2.5)$(4.3)$— 
(a)Includes mutual fund investments of approximately 25% in common stock of large-cap U.S. companies, 5% in common stock of small to mid-cap U.S. companies, 10% in international companies, 15% in bond funds, 5% in short-term investments and 40% in blended funds.

 September 30,
2022		 
Level One		 
Level Two		 
Level Three
Asset Class:
Mutual fund investments in a non-qualified savings plan(a)
$1.8 $1.8 $— $— 
Total Assets$1.8 $1.8 $— $— 
Liability Class:    
Derivatives – natural gas instruments, net$(1.1)$— $(1.1)$— 
Liabilities related to non-qualified savings plan(1.8)(1.8)— — 
Total Liabilities$(2.9)$(1.8)$(1.1)$— 
(a)Includes mutual fund investments of approximately 30% in the common stock of large-cap U.S. companies, 5% in the common stock of small to mid-cap U.S. companies, 10% in the common stock of international companies, 15% in bond funds, 5% in short-term investments and 35% in blended funds.
v3.22.4
Earnings per Share (Tables)
 3 Months Ended
Dec. 31, 2022
Earnings Per Share [Abstract]  
Summary of Basic and Diluted Earnings Per Common Share The following table sets forth the computation of basic and diluted earnings per common share (in millions, except for share and per-share data):
 Three Months Ended
December 31,
 20222021
Numerator:
Net (loss) earnings from continuing operations$(0.3)$7.9 
Less: net earnings allocated to participating securities(a)
(0.1)(0.1)
Net (loss) earnings from continuing operations available to common stockholders(0.4)7.8 
Net loss from discontinued operations available to common stockholders— (5.5)
Net (loss) earnings available to common stockholders$(0.4)$2.3 
Denominator (in thousands):
Weighted-average common shares outstanding, shares for basic earnings per share39,751 34,060 
Weighted-average awards outstanding(b)
— 29 
Shares for diluted earnings per share39,751 34,089 
Basic net (loss) earnings from continuing operations per common share$(0.01)$0.23 
Basic net loss from discontinued operations per common share— (0.16)
Basic net (loss) earnings per common share$(0.01)$0.07 
Diluted net (loss) earnings from continuing operations per common share$(0.01)$0.23 
Diluted net loss from discontinued operations per common share— (0.16)
Diluted net (loss) earnings per common share$(0.01)$0.07 
(a)Weighted participating securities include RSUs and PSUs that receive non-forfeitable dividends and consist of 514,000 weighted participating securities for the three months ended December 31, 2022, and 430,000 weighted participating securities for the three months ended December 31, 2021.
(b)For the calculation of diluted net earnings per share, the Company uses the more dilutive of either the treasury stock method or the two-class method to determine the weighted-average number of outstanding common shares. In addition, the Company had 1,272,000 weighted-average equity awards outstanding for the three months ended December 31, 2022, and 1,097,000 weighted-average equity awards outstanding for the three months ended December 31, 2021, that were anti-dilutive.
v3.22.4
Discontinued Operations - Narrative (Details)
R$ in Millions, $ in Millions
 3 Months Ended
Dec. 31, 2022
BRL (R$)
Apr. 20, 2022
USD ($)
Aug. 20, 2021
USD ($)
Jul. 01, 2021
USD ($)
Jun. 28, 2021
BRL (R$)
Dec. 31, 2022
USD ($)
Dec. 31, 2021
USD ($)
Apr. 07, 2022
USD ($)
May 04, 2021
USD ($)
Mar. 23, 2021
BRL (R$)
Fermavi                    
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]                    
Deferred purchase price | R$ R$ 22.5       R$ 30.0          
Potential proceeds from sale of investments     $ 2.9   R$ 45.0          
Deferred proceeds receivable     $ 4.8              
Discontinued Operations, Held-for-sale or Disposed of by Sale                    
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]                    
Gain (loss) on disposal             $ (8.4)      
Release of accumulated currency translation adjustment             $ (3.1)      
Discontinued Operations, Held-for-sale or Disposed of by Sale | Plant Nutrition South America                    
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]                    
Proceeds from sale of business       $ 318.4            
Additional earn out payment               $ 18.5   R$ 88.0
Discontinued Operations, Held-for-sale or Disposed of by Sale | North America Micronutrient Assets                    
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]                    
Gross proceeds received                 $ 56.7  
Discontinued Operations, Held-for-sale or Disposed of by Sale | South America Chemicals Business                    
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]                    
Gross proceeds received   $ 51.5                
Cash on hand   6.4                
Selling costs   2.4                
Loss recovery on sale           $ 1.6        
Gain (loss) on disposal           $ (23.1)        
Release of accumulated currency translation adjustment   $ 49.5                
v3.22.4
Discontinued Operations - Schedule of Discontinued Operations (Details) - USD ($)
$ in Millions
 3 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]    
Net loss from discontinued operations $ 0.0 $ (5.5)
Discontinued Operations, Held-for-sale or Disposed of by Sale    
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]    
Sales   22.4
Gross profit   10.3
Selling, general and administrative expenses   1.6
Operating earnings   8.7
Loss on foreign exchange   3.1
Net loss on adjustment to fair value less estimated costs to sell   8.4
Other income, net   (0.2)
Loss from discontinued operations before income taxes   (2.6)
Income tax expense   2.9
Net loss from discontinued operations   (5.5)
Disposal Group, Including Discontinued Operation, Additional Disclosures [Abstract]    
Loss on impairment of long-lived assets   8.4
Capital expenditures   (0.7)
Discontinued Operations, Held-for-sale or Disposed of by Sale | Shipping and handling cost    
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]    
Cost of goods and services sold   1.2
Discontinued Operations, Held-for-sale or Disposed of by Sale | Product cost    
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]    
Cost of goods and services sold   $ 10.9
v3.22.4
Revenues (Details)
 3 Months Ended
Dec. 31, 2022
Revenue from Contract with Customer [Abstract]  
Payment terms for delivery 30 days
v3.22.4
Inventories (Details) - USD ($)
$ in Millions
Dec. 31, 2022
Sep. 30, 2022
Inventory Disclosure [Abstract]    
Finished goods $ 242.3 $ 251.6
Raw materials and supplies 58.7 52.8
Total inventories $ 301.0 $ 304.4
v3.22.4
Property, Plant and Equipment, Net (Details) - USD ($)
$ in Millions
Dec. 31, 2022
Sep. 30, 2022
Property, Plant and Equipment [Line Items]    
Total property plant and equipment $ 1,874.8 $ 1,849.3
Less: accumulated depreciation and depletion (1,100.0) (1,072.7)
Property, plant and equipment, net 774.8 776.6
Land, buildings and structures, and leasehold improvements    
Property, Plant and Equipment [Line Items]    
Total property plant and equipment 543.0 534.8
Machinery and equipment    
Property, Plant and Equipment [Line Items]    
Total property plant and equipment 1,058.2 1,026.3
Office furniture and equipment    
Property, Plant and Equipment [Line Items]    
Total property plant and equipment 56.9 56.8
Mineral interests    
Property, Plant and Equipment [Line Items]    
Total property plant and equipment 168.7 167.1
Construction in progress    
Property, Plant and Equipment [Line Items]    
Total property plant and equipment $ 48.0 $ 64.3
v3.22.4
Goodwill and Intangible Assets, Net (Details) - USD ($)
$ in Millions
 3 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Sep. 30, 2022
Goodwill [Line Items]      
Aggregate amortization expense $ 0.4 $ 0.4  
Goodwill 56.8   $ 56.4
Other      
Goodwill [Line Items]      
Goodwill 5.8   5.5
Plant Nutrition | Operating Segments      
Goodwill [Line Items]      
Goodwill $ 51.0   $ 50.9
v3.22.4
Equity Method Investments - Narrative (Details) - USD ($)
$ in Millions
 3 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Sep. 30, 2022
Schedule of Equity Method Investments [Line Items]      
Net loss in equity investee $ (0.9) $ (0.4)  
Equity method investments 45.7   $ 46.6
Fortress      
Schedule of Equity Method Investments [Line Items]      
Investment in investee $ 50.0    
Ownership interest in investment 45.00%    
Net loss in equity investee $ 0.5 0.1  
Basis difference 27.0    
Equity method investments 45.3   45.8
Other Immaterial Investments      
Schedule of Equity Method Investments [Line Items]      
Net loss in equity investee 0.4 $ 0.3  
Equity method investments $ 0.4   $ 0.8
v3.22.4
Income Taxes (Details) - USD ($)
$ in Millions
 3 Months Ended
Dec. 31, 2022
Sep. 30, 2022
Income Tax Disclosure [Line Items]    
Nondeductible executive compensation $ 1.0  
U.S. Federal    
Income Tax Disclosure [Line Items]    
Deferred tax asset valuation allowance recorded 6.1  
Foreign Tax Authority    
Income Tax Disclosure [Line Items]    
Net operating loss carryforwards 87.2 $ 94.1
Foreign Tax Authority | Canadian Tax Authority    
Income Tax Disclosure [Line Items]    
Total reassessments including interest 170.2  
Amount of security posted in the form of a performance bond 143.4  
Amount of security posted in the form of cash 36.7 36.7
State and Local | NOL carryforwards expire beginning in 2027    
Income Tax Disclosure [Line Items]    
Net operating loss carryforwards $ 3.2 $ 3.2
v3.22.4
Long-Term Debt (Details) - USD ($)
$ in Millions
 3 Months Ended
Dec. 31, 2022
Sep. 30, 2022
Debt Instrument [Line Items]    
Long-term debt, gross $ 839.8 $ 955.9
Less unamortized debt issuance costs (7.7) (8.3)
Total debt 832.1 947.6
Less current portion 0.0 0.0
Long-term debt $ 832.1 947.6
Weighted average interest rate of debt (as a percent) 6.40%  
Quarter ending December 31, 2022    
Debt Instrument [Line Items]    
Consolidated total net leverage ratio 500.00%  
Quarter ending March 31, 2024    
Debt Instrument [Line Items]    
Consolidated total net leverage ratio 475.00%  
Fiscal quarter ended June 30, 2024    
Debt Instrument [Line Items]    
Consolidated total net leverage ratio 450.00%  
Term Loan due January 2025    
Debt Instrument [Line Items]    
Long-term debt, gross $ 16.9 $ 16.9
Senior Notes | 4.875% Senior Notes due July 2024    
Debt Instrument [Line Items]    
Stated interest rate (as a percent) 4.875% 4.875%
Long-term debt, gross $ 250.0 $ 250.0
Senior Notes | 6.75% Senior Notes due December 2027    
Debt Instrument [Line Items]    
Stated interest rate (as a percent) 6.75% 6.75%
Long-term debt, gross $ 500.0 $ 500.0
Line of Credit | AR Securitization Facility expires June 2025    
Debt Instrument [Line Items]    
Long-term debt, gross 72.9 37.5
Line of Credit | Revolving Credit Facility due January 2025 | Revolving Credit Facility due January 2025    
Debt Instrument [Line Items]    
Long-term debt, gross 0.0 $ 151.5
Maximum unrestricted cash $ 50.0  
v3.22.4
Commitments and Contingencies (Details) - SEC Investigation - USD ($)
$ in Millions
Sep. 29, 2022
Sep. 23, 2022
Loss Contingencies [Line Items]    
Loss contingency, damages sought, value   $ 12
Loss contingency, damages paid, value $ 2  
Contingent loss accrual   $ 10
v3.22.4
Operating Segments (Details)
$ in Millions
 3 Months Ended
Dec. 31, 2022
USD ($)
segment
Dec. 31, 2021
USD ($)
Segment Reporting [Abstract]    
Number of reportable segments | segment 2  
Segment Reporting Information [Abstract]    
Sales $ 352.4 $ 331.5
Operating earnings (loss) 27.9 20.4
Depreciation, depletion and amortization 23.9 28.3
Total assets (as of end of period) 1,764.7 1,687.4
Costs related to ongoing SEC investigation 0.3 3.1
Executive transition costs   3.3
United States    
Segment Reporting Information [Abstract]    
Sales 248.2 221.3
Canada    
Segment Reporting Information [Abstract]    
Sales 87.6 89.4
United Kingdom    
Segment Reporting Information [Abstract]    
Sales 14.1 19.8
Other    
Segment Reporting Information [Abstract]    
Sales 2.5 1.0
Shipping and handling cost    
Segment Reporting Information [Abstract]    
Shipping and handling cost 107.4 95.7
Highway Deicing Salt    
Segment Reporting Information [Abstract]    
Sales 190.3 163.7
Consumer & Industrial Salt    
Segment Reporting Information [Abstract]    
Sales 117.8 110.2
SOP    
Segment Reporting Information [Abstract]    
Sales 44.5 57.0
Eliminations & Other    
Segment Reporting Information [Abstract]    
Sales (0.2) 0.6
Operating Segments | Salt    
Segment Reporting Information [Abstract]    
Sales 308.1 273.9
Operating earnings (loss) 47.1 39.4
Depreciation, depletion and amortization 13.9 16.2
Total assets (as of end of period) 985.2 1,035.4
Operating Segments | Salt | Shipping and handling cost    
Segment Reporting Information [Abstract]    
Shipping and handling cost 102.7 88.4
Operating Segments | Salt | Highway Deicing Salt    
Segment Reporting Information [Abstract]    
Sales 190.3 163.7
Operating Segments | Salt | Consumer & Industrial Salt    
Segment Reporting Information [Abstract]    
Sales 117.8 110.2
Operating Segments | Salt | SOP    
Segment Reporting Information [Abstract]    
Sales 0.0 0.0
Operating Segments | Salt | Eliminations & Other    
Segment Reporting Information [Abstract]    
Sales 0.0 0.0
Operating Segments | Plant Nutrition    
Segment Reporting Information [Abstract]    
Sales 41.6 54.6
Operating earnings (loss) 11.0 9.5
Depreciation, depletion and amortization 8.3 8.8
Total assets (as of end of period) 456.5 445.3
Operating Segments | Plant Nutrition | Shipping and handling cost    
Segment Reporting Information [Abstract]    
Shipping and handling cost 4.7 7.3
Operating Segments | Plant Nutrition | Highway Deicing Salt    
Segment Reporting Information [Abstract]    
Sales 0.0 0.0
Operating Segments | Plant Nutrition | Consumer & Industrial Salt    
Segment Reporting Information [Abstract]    
Sales 0.0 0.0
Operating Segments | Plant Nutrition | SOP    
Segment Reporting Information [Abstract]    
Sales 44.5 57.0
Operating Segments | Plant Nutrition | Eliminations & Other    
Segment Reporting Information [Abstract]    
Sales (2.9) (2.4)
Corporate & Other    
Segment Reporting Information [Abstract]    
Sales 2.7 3.0
Operating earnings (loss) (30.2) (28.5)
Depreciation, depletion and amortization 1.7 3.3
Total assets (as of end of period) 323.0 206.7
Corporate & Other | Shipping and handling cost    
Segment Reporting Information [Abstract]    
Shipping and handling cost 0.0 0.0
Corporate & Other | Highway Deicing Salt    
Segment Reporting Information [Abstract]    
Sales 0.0 0.0
Corporate & Other | Consumer & Industrial Salt    
Segment Reporting Information [Abstract]    
Sales 0.0 0.0
Corporate & Other | SOP    
Segment Reporting Information [Abstract]    
Sales 0.0 0.0
Corporate & Other | Eliminations & Other    
Segment Reporting Information [Abstract]    
Sales 2.7 3.0
Intersegment Eliminations    
Segment Reporting Information [Abstract]    
Sales (2.9) (2.4)
Intersegment Eliminations | Salt    
Segment Reporting Information [Abstract]    
Sales 0.0 0.0
Intersegment Eliminations | Plant Nutrition    
Segment Reporting Information [Abstract]    
Sales $ 2.9 $ 2.4
v3.22.4
Stockholders' Equity and Equity Instruments - Narrative (Details) - USD ($)
$ / shares in Units, $ in Millions
 1 Months Ended 3 Months Ended 12 Months Ended
Oct. 18, 2022
Sep. 14, 2022
Feb. 28, 2022
Dec. 31, 2022
Dec. 31, 2021
Sep. 30, 2021
May 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Treasury stock reissued (in shares)           117,390  
Tax deficiency from equity compensation awards recorded as an increase to income tax expense       $ 0.1      
Compensation expense recorded during period pursuant to stock-based compensation plans       $ 10.6 $ 4.7    
Compensation expense to be paid in cash         $ 1.4    
Koch Minerals & Trading, LLC              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Ownership by noncontrolling interest (as a percent) 17.00%            
Private Placement              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of shares issued   6,830,700          
Sale of Stock, Price (in dollars per share)   $ 36.87          
Net proceeds   $ 240.7          
Advancement of development project $ 200.0            
Portion to reduce debt $ 40.7            
Stock Options              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Vesting period       4 years      
Options expiration period       7 years      
Number of shares available from conversion (in shares)       1      
RSUs              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of shares available from conversion (in shares)       1      
Reissued shares of treasury stock (in shares)       31,140      
TSR PSUs | Minimum              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Performance period of PSUs       2 years      
Percentage of shares earned       0.00%      
TSR PSUs | Maximum              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Performance period of PSUs       3 years      
Percentage of shares earned       300.00%      
EBITDA Growth PSUs | Minimum              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Percentage of shares earned       0.00%      
EBITDA Growth PSUs | Maximum              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Percentage of shares earned       300.00%      
Stock Payments              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Reissued shares of treasury stock (in shares)       936      
Equity Awards              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Shares withheld related to vesting of RSUs and PSUs (in shares)       9,853      
Fair value of stock withheld related to vesting of RSUs and PSUs       $ 0.4      
2020 Incentive Award Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Shares authorized for issuance (in shares)             2,977,933
Shares authorized for issuance (in shares)     750,000        
2020 Incentive Award Plan | RSUs              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Service period       3 years      
2015 Incentive Award Plan | RSUs              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Service period       1 year      
v3.22.4
Stockholders' Equity and Equity Instruments - Stock-Based Compensation Activity (Details)
 3 Months Ended
Dec. 31, 2022
$ / shares
shares
Stock Options  
Number  
Outstanding at beginning of period (in shares) 774,580
Granted (in shares) 0
Exercised (in shares) 0
Released from restriction (in shares) 0
Cancelled/expired (in shares) (13,241)
Outstanding at end of period (in shares) 761,339
Weighted-average exercise price  
Weighted-average exercise price at beginning of period (in dollars per share) | $ / shares $ 60.68
Weighted-average exercise price, granted (in dollars per share) | $ / shares 0
Weighted-average exercise price, exercised (in dollars per share) | $ / shares 0
Weighted-average exercise price, released from restriction (in dollars per share) | $ / shares 0
Weighted-average exercise price, cancelled/expired (in dollars per share) | $ / shares 62.57
Weighted-average exercise price at end of period (in dollars per share) | $ / shares $ 60.64
RSUs  
Number  
Outstanding at beginning of period (in shares) 208,735
Granted (in shares) 221,151
Exercised (in shares) 0
Released from restriction (in shares) (31,755)
Cancelled/expired (in shares) (4,496)
Outstanding at end of period (in shares) 393,635
Weighted-average fair value  
Weighted-average fair value at beginning of period (in dollars per share) | $ / shares $ 63.02
Weighted-average fair value, granted (in dollars per share) | $ / shares 38.14
Weighted-average fair value, exercised (in dollars per share) | $ / shares 0
Weighted-average fair value, released from restriction (in dollars per share) | $ / shares 67.61
Weighted-average fair value, cancelled/expired (in dollars per share) | $ / shares 46.27
Weighted-average fair value at end of period (in dollars per share) | $ / shares $ 48.86
PSUs  
Number  
Outstanding at beginning of period (in shares) 331,359
Granted (in shares) 182,422
Exercised (in shares) 0
Released from restriction (in shares) 0
Cancelled/expired (in shares) 0
Outstanding at end of period (in shares) 513,781
Weighted-average fair value  
Weighted-average fair value at beginning of period (in dollars per share) | $ / shares $ 71.51
Weighted-average fair value, granted (in dollars per share) | $ / shares 68.29
Weighted-average fair value, exercised (in dollars per share) | $ / shares 0
Weighted-average fair value, released from restriction (in dollars per share) | $ / shares 0
Weighted-average fair value, cancelled/expired (in dollars per share) | $ / shares 0
Weighted-average fair value at end of period (in dollars per share) | $ / shares $ 70.37
PSU at grant date (in shares per unit) 1
v3.22.4
Stockholders' Equity and Equity Instruments - Components and Changes In AOCL (Details) - USD ($)
$ in Millions
 3 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Beginning balance $ 256.4 $ 293.1
Other comprehensive (loss) income before reclassifications 9.3 (4.7)
Amounts reclassified from accumulated other comprehensive loss (0.3) (1.0)
Net current period other comprehensive (loss) income 9.0 (5.7)
Ending balance 509.8 288.0
Gains (loss) on foreign exchange of intercompany notes of long-term nature (1.3) 1.2
Losses on Cash Flow Hedges    
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Beginning balance (1.6) 3.1
Other comprehensive (loss) income before reclassifications (2.4) (0.9)
Amounts reclassified from accumulated other comprehensive loss (0.4) (1.1)
Net current period other comprehensive (loss) income (2.8) (2.0)
Ending balance (4.4) 1.1
Benefit Plans    
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Beginning balance   (5.4)
Other comprehensive (loss) income before reclassifications   0.0
Amounts reclassified from accumulated other comprehensive loss   0.1
Net current period other comprehensive (loss) income   0.1
Ending balance   (5.3)
Benefit Plans | Defined Benefit Pension    
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Beginning balance (2.7)  
Other comprehensive (loss) income before reclassifications 0.0  
Amounts reclassified from accumulated other comprehensive loss 0.1  
Net current period other comprehensive (loss) income 0.1  
Ending balance (2.6)  
Benefit Plans | Other Post-Employment Benefits    
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Beginning balance 1.3  
Other comprehensive (loss) income before reclassifications 0.0  
Amounts reclassified from accumulated other comprehensive loss 0.0  
Net current period other comprehensive (loss) income 0.0  
Ending balance 1.3  
Foreign Currency    
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Beginning balance (112.3) (108.2)
Other comprehensive (loss) income before reclassifications 11.7 (3.8)
Amounts reclassified from accumulated other comprehensive loss 0.0 0.0
Net current period other comprehensive (loss) income 11.7 (3.8)
Ending balance (100.6) (112.0)
Total    
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]    
Beginning balance (115.3) (110.5)
Ending balance $ (106.3) $ (116.2)
v3.22.4
Stockholders' Equity and Equity Instruments - Reclassifications From AOCL (Details) - USD ($)
$ in Millions
 3 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]    
Income tax benefit (expense) $ 11.9 $ (1.2)
Net (loss) earnings (0.3) 2.4
Product cost    
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]    
Product cost (175.0) (175.9)
Amount Reclassified from AOCL    
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]    
Net (loss) earnings (0.3) (1.0)
Amount Reclassified from AOCL | Losses on cash flow hedges:    
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]    
Income tax benefit (expense) 0.1 0.4
Net (loss) earnings (0.4) (1.1)
Amount Reclassified from AOCL | Losses on cash flow hedges: | Natural gas instruments | Product cost    
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]    
Product cost (0.5) (1.5)
Amount Reclassified from AOCL | Amortization of defined benefit pension:    
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]    
Income tax benefit (expense) 0.0 0.0
Net (loss) earnings 0.1 0.1
Amount Reclassified from AOCL | Amortization of defined benefit pension: | Product cost    
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]    
Product cost 0.1 0.1
Amount Reclassified from AOCL | Amortization of other post-employment benefits:    
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]    
Income tax benefit (expense) 0.0 0.0
Net (loss) earnings 0.0 0.0
Amount Reclassified from AOCL | Amortization of other post-employment benefits: | Product cost    
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]    
Product cost $ 0.0 $ 0.0
v3.22.4
Derivative Financial Instruments - Narrative (Details) - Natural gas instruments
MMBTU in Millions, $ in Millions
 3 Months Ended 12 Months Ended
Dec. 31, 2022
USD ($)
MMBTU
Sep. 30, 2022
MMBTU
Derivatives, Fair Value [Line Items]    
Notional amount (in MMBtus) | MMBTU 3.1 3.8
Net gains to be reclassified from accumulated other comprehensive loss to earnings during the next 12 months | $ $ 3.7  
Derivatives Designated as Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Percent of forecasted usage to be hedged 90.00%  
Maximum period which the Company hedges in advance of forecasted purchase 36 months  
v3.22.4
Derivative Financial Instruments - Fair Value of Hedged Items (Details) - USD ($)
$ in Millions
Dec. 31, 2022
Sep. 30, 2022
Derivatives Designated as Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Asset Derivatives $ 1.7 $ 2.9
Liability Derivatives 6.0 4.0
Natural gas instruments    
Derivatives, Fair Value [Line Items]    
Netting of contracts in a receivable position against contracts in payable position 1.7 2.9
Other current assets | Natural gas instruments | Derivatives Designated as Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Asset Derivatives 1.6 2.7
Other assets | Natural gas instruments | Derivatives Designated as Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Asset Derivatives 0.1 0.2
Accrued expenses and other current liabilities | Natural gas instruments | Derivatives Designated as Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Liability Derivatives 5.2 3.3
Other noncurrent liabilities | Natural gas instruments | Derivatives Designated as Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Liability Derivatives $ 0.8 $ 0.7
v3.22.4
Fair Value Measurements - Summary of Estimated Fair Values (Details) - USD ($)
$ in Millions
 3 Months Ended 12 Months Ended
Dec. 31, 2022
Sep. 30, 2022
Common Stock, Large Cap US Companies | Mutual Fund Investments, Concentration Risk | Investment Benchmark    
Liability Class:    
Investment concentration risk (as a percent) 25.00% 30.00%
Common Stock of Small to Mid Cap US Companies | Mutual Fund Investments, Concentration Risk | Investment Benchmark    
Liability Class:    
Investment concentration risk (as a percent) 5.00% 5.00%
Common Stock, International Companies | Mutual Fund Investments, Concentration Risk | Investment Benchmark    
Liability Class:    
Investment concentration risk (as a percent) 10.00% 10.00%
Bond Funds | Mutual Fund Investments, Concentration Risk | Investment Benchmark    
Liability Class:    
Investment concentration risk (as a percent) 15.00% 15.00%
Short-Term Investments | Mutual Fund Investments, Concentration Risk | Investment Benchmark    
Liability Class:    
Investment concentration risk (as a percent) 5.00% 5.00%
Blended Funds | Mutual Fund Investments, Concentration Risk | Investment Benchmark    
Liability Class:    
Investment concentration risk (as a percent) 40.00% 35.00%
Fair Value, Measurements, Recurring    
Asset Class:    
Mutual fund investments in a non-qualified savings plan $ 2.5 $ 1.8
Total Assets 2.5 1.8
Liability Class:    
Derivatives - natural gas instruments, net (4.3) (1.1)
Liabilities related to non-qualified savings plan (2.5) (1.8)
Total Liabilities (6.8) (2.9)
Fair Value, Measurements, Recurring | Level One    
Asset Class:    
Mutual fund investments in a non-qualified savings plan 2.5 1.8
Total Assets 2.5 1.8
Liability Class:    
Derivatives - natural gas instruments, net 0.0 0.0
Liabilities related to non-qualified savings plan (2.5) (1.8)
Total Liabilities (2.5) (1.8)
Fair Value, Measurements, Recurring | Level Two    
Asset Class:    
Mutual fund investments in a non-qualified savings plan 0.0 0.0
Total Assets 0.0 0.0
Liability Class:    
Derivatives - natural gas instruments, net (4.3) (1.1)
Liabilities related to non-qualified savings plan 0.0 0.0
Total Liabilities (4.3) (1.1)
Fair Value, Measurements, Recurring | Level Three    
Asset Class:    
Mutual fund investments in a non-qualified savings plan 0.0 0.0
Total Assets 0.0 0.0
Liability Class:    
Derivatives - natural gas instruments, net 0.0 0.0
Liabilities related to non-qualified savings plan 0.0 0.0
Total Liabilities $ 0.0 $ 0.0
v3.22.4
Fair Value Measurements - Narrative (Details) - USD ($)
Dec. 31, 2022
Sep. 30, 2022
Senior Notes | 4.875% Senior Notes due July 2024    
Debt Instrument [Line Items]    
Stated interest rate (as a percent) 4.875% 4.875%
Fair value of senior notes $ 239,900,000 $ 235,900,000
Aggregate principal amount due at maturity $ 250,000,000 $ 250,000,000
Senior Notes | 6.75% Senior Notes due December 2027    
Debt Instrument [Line Items]    
Stated interest rate (as a percent) 6.75% 6.75%
Fair value of senior notes $ 479,400,000 $ 468,900,000
Senior Notes due 2027    
Debt Instrument [Line Items]    
Debt fair value amount 500,000,000 500,000,000
Term Loan    
Debt Instrument [Line Items]    
Aggregate principal amount due at maturity 16,900,000 168,400,000
Fair value of credit agreement debt 16,800,000 158,500,000
Fair Value, Measurements, Recurring    
Debt Instrument [Line Items]    
Mutual fund investments in a non-qualified savings plan 2,500,000 1,800,000
Fair Value, Measurements, Recurring | Level One    
Debt Instrument [Line Items]    
Mutual fund investments in a non-qualified savings plan $ 2,500,000 $ 1,800,000
v3.22.4
Earnings per Share (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Millions
 3 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Numerator:    
Net (loss) earnings from continuing operations $ (0.3) $ 7.9
Less: net loss allocated to participating securities (0.1) (0.1)
Net (loss) earnings from continuing operations available to common stockholders (0.4) 7.8
Net loss from discontinued operations available to common stockholders 0.0 (5.5)
Net (loss) earnings available to common stockholders $ (0.4) $ 2.3
Denominator (in thousands):    
Weighted-average common shares outstanding, shares for basic earnings per share (in shares) 39,751 34,060
Weighted-average awards outstanding (in shares) 0 29
Shares for diluted earnings per share (in shares) 39,751 34,089
Basic net (loss) earnings from continuing operations per common share (in dollars per share) $ (0.01) $ 0.23
Basic net loss from discontinued operations per common share (in dollars per share) 0 (0.16)
Basic net (loss) earnings per common share (in dollars per share) (0.01) 0.07
Diluted net (loss) earnings from continuing operations per common share (in dollars per share) (0.01) 0.23
Diluted net loss from discontinued operations per common share (in dollars per share) 0 (0.16)
Diluted net (loss) earnings per common share (in dollars per share) $ (0.01) $ 0.07
Participating securities (in shares) 514,000 430,000
Stock Options    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Anti-dilutive weighted options outstanding (in shares) 1,272,000 1,097,000
v3.22.4
Related Party Disclosures (Details)
$ / shares in Units, $ in Millions
 3 Months Ended
Dec. 20, 2022
USD ($)
$ / shares
Dec. 31, 2022
USD ($)
Dec. 31, 2021
USD ($)
Nov. 13, 2022
board_member
Oct. 18, 2022
Related Party Transaction [Line Items]          
Number of board members | board_member       2  
Cash dividend declared (in dollars per share) | $ / shares $ 0.15        
Payments of dividends $ 6.3 $ 6.3 $ 5.3    
Koch Minerals & Trading, LLC          
Related Party Transaction [Line Items]          
Revenue   0.9 0.7    
Accounts receivable   0.5 $ 0.4    
Capitalized cost   0.5      
Accounts payable   $ 0.3      
Payments of dividends $ 1.0        
Koch Minerals & Trading, LLC          
Related Party Transaction [Line Items]          
Ownership by noncontrolling interest (as a percent)         17.00%