| Summary of Significant Accounting Policies (Policies) | 12 Months Ended |
| Dec. 31, 2024 |
| Accounting Policies [Abstract] | |
| Basis of Presentation | Basis of Presentation |
| Newly Adopted Accounting Standards and Accounting Standards Not Yet Implemented | Newly Adopted Accounting Standards Segments. In November 2023, Accounting Standards Update (ASU) 2023-07 was issued, which requires public entities to provide in interim periods, following adoption, all disclosures about a reportable segment’s profit or loss that are currently required annually; disclose significant segment expense categories and amounts that are easily computable from the management reports that are regularly provided to the chief operating decision maker (CODM); disclose how the CODM uses each reported measure to assess performance and allocate resources; and disclose the title of the position of the individual identified as the CODM. The Company adopted the amendments effective December 31, 2024, and applied the amendments retrospectively to all prior periods presented in the consolidated financial statements. The adoption of this ASU impacted its disclosures in Note 22. “Segment and Geographic Information,” with no impacts to its consolidated results of operations, cash flows and financial condition. Accounting Standards Not Yet Implemented Income Taxes . In December 2023, ASU 2023-09 was issued, which requires public entities to disclose more information primarily related to the income tax rate reconciliation and income taxes paid. The guidance also eliminates certain existing disclosure requirements related to uncertain tax positions and unrecognized deferred tax liabilities. The Company is required to adopt the amendments for fiscal years beginning after December 15, 2024. The amendments should be applied prospectively, with a retrospective option. Early adoption is permitted. The Company expects this ASU to only impact its disclosures with no impacts to its consolidated results of operations, cash flows and financial condition. Expense Disaggregation . In November 2024, ASU 2024-03 was issued, which requires public entities to disclose additional information about specific expense categories in the notes to financial statements at interim and annual reporting periods. The Company is required to adopt the amendments for fiscal years beginning after December 15, 2026 and interim reporting periods beginning after December 15, 2027. The amendments should be applied prospectively, with a retrospective option. Early adoption is permitted. The Company expects this ASU to only impact its disclosures with no impacts to its consolidated results of operations, cash flows and financial condition. Induced Conversions of Convertible Debt |
| Revenues | Revenue The majority of the Company’s revenue is derived from the sale of coal under long-term coal supply agreements (those with initial terms of one year or longer and which often include price reopener and/or extension provisions) and contracts with terms of less than one year, including sales made on a spot basis. The Company’s revenue from coal sales is realized and earned when control passes to the customer. Under the typical terms of the Company’s coal supply agreements, title and risk of loss transfer to the customer at the mine or port, where coal is loaded to the transportation sources that serve the Company’s mines. The Company incurs certain “add-on” taxes and fees on coal sales. Reported coal sales include taxes and fees charged by various federal and state governmental bodies and the freight charged on destination customer contracts. The Company’s seaborne operating platform is primarily export focused with customers spread across several countries, with a portion of the thermal and metallurgical coal sold within Australia. Generally, revenue from individual countries vary year by year based on electricity and steel demand, the strength of the global economy, governmental policies and several other factors, including those specific to each country. A majority of these sales are executed through annual and multi-year international coal supply agreements that contain provisions requiring both parties to renegotiate pricing periodically. Industry commercial practice, and the Company’s typical practice, is to negotiate pricing for seaborne thermal coal contracts on an annual, spot or index basis and seaborne metallurgical coal contracts on a quarterly, spot or index basis. In the case of periodically negotiated pricing, the Company may deliver coal under provisional pricing until a final agreed-upon price is determined. Variable consideration resulting from provisional pricing arrangements is recognized based on the Company’s best estimate of the amount expected to be received at the time control is transferred to the customer that is not expected to result in a material reversal of revenue. The Company’s U.S. thermal operating platform primarily sells thermal coal to electric utilities in the U.S. under long-term contracts, with a portion sold into the seaborne markets as conditions warrant. A significant portion of the coal production from the U.S. thermal operating segments is sold under existing long-term supply agreements. Certain customers of those segments utilize long-term sales agreements in recognition of the importance of reliability, service and predictable coal prices to their operations. The terms of coal supply agreements result from competitive bidding and extensive negotiations with customers. Consequently, the terms of those agreements may vary in many respects, including price adjustment features, price reopener terms, coal quality requirements, quantity parameters, permitted sources of supply, treatment of environmental constraints, extension options, force majeure and termination and assignment provisions. Contract pricing is set forth on a per ton basis, and revenue is generally recorded as the product of price and volume delivered. Many of the Company’s coal supply agreements contain provisions that permit the parties to adjust the contract price upward or downward at specified times. These contract prices may be adjusted based on inflation or deflation and/or changes in the factors affecting the cost of producing coal, such as taxes, fees, royalties and changes in the laws regulating the mining, production, sale or use of coal. In a limited number of contracts, failure of the parties to agree on a price under those provisions may allow either party to terminate the contract. The Company sometimes experiences a reduction in coal prices in new long-term coal supply agreements replacing some of its expiring contracts. Coal supply agreements also typically contain force majeure provisions allowing temporary suspension of performance by the Company or the customer during the duration of specified events beyond the control of the affected party. Most of the coal supply agreements contain provisions requiring the Company to deliver coal meeting quality thresholds for certain characteristics such as Btu, sulfur content, ash content, grindability and ash fusion temperature. Failure to meet these specifications could result in economic penalties, including price adjustments, the rejection of deliveries or termination of the contracts. Moreover, some of these agreements allow the Company’s customers to terminate their contracts in the event of changes in regulations affecting the industry that restrict the use or type of coal permissible at the customer’s plant or increase the price of coal beyond specified limits. |
| Discontinued Operations | Discontinued Operations The Company classifies items within discontinued operations in the consolidated financial statements when the operations and cash flows of a particular component of the Company have been (or will be) eliminated from the ongoing operations of the Company as a result of a disposal (by sale or otherwise) and represents a strategic shift that has (or will have) a major effect on the entity’s operations and financial results. Discontinued operations include certain former Seaborne Thermal and Other U.S. Thermal segment assets that have ceased production and other previously divested legacy operations, including Patriot Coal Corporation and certain of its wholly-owned subsidiaries (Patriot). On August 8, 2023, the Company entered into a settlement agreement with the U.S. Department of Labor to resolve a liability dispute regarding the federal black lung claims of Patriot. In accordance with the settlement agreement, the Company paid $72.0 million to settle the Patriot federal black lung claims, with the exception of approximately $4.2 million of certain claims for attorney’s fees and additional compensation due to claimants not paid during appeal. As a result of the settlement, the Company recognized a $3.9 million gain within “(Loss) income from discontinued operations, net of income taxes” during the year ended December 31, 2023. |
| Assets and Liabilities Held for Sale | Assets and Liabilities Held for Sale The Company classifies assets and liabilities (disposal groups) to be sold as held for sale in the period in which all of the following criteria are met: management, having the authority to approve the action, commits to a plan to sell the disposal group; the disposal group is available for immediate sale in its present condition subject only to terms that are usual and customary for sales of such disposal groups; an active program to locate a buyer and other actions required to complete the plan to sell the disposal group have been initiated; the sale of the disposal group is probable, and transfer of the disposal group is expected to qualify for recognition as a completed sale within one year, except if events or circumstances beyond the Company's control extend the period of time required to sell the disposal group beyond one year; the disposal group is being actively marketed for sale at a price that is reasonable in relation to its current fair value; and actions required to complete the plan indicate that it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn. The Company initially measures a disposal group that is classified as held for sale at the lower of its carrying value or fair value less any costs to sell. Any loss resulting from this measurement is recognized in the period in which the held for sale criteria are met. Conversely, gains are not recognized on the sale of a disposal group until the date of sale. The Company assesses the fair value of a disposal group, less any costs to sell, each reporting period it remains classified as held for sale and reports any subsequent changes as an adjustment to the carrying value of the disposal group, as long as the new carrying value does not exceed the carrying value of the disposal group at the time it was initially classified as held for sale. |
| Cash and Cash Equivalents | Cash and Cash Equivalents Cash and cash equivalents are stated at cost, which approximates fair value. Cash equivalents consist of highly liquid investments with original maturities of three months or less. |
| Accounts Receivable | Accounts Receivable The timing of revenue recognition, billings and cash collections results in accounts receivable from customers. Customers are invoiced as coal is shipped or at periodic intervals in accordance with contractual terms. Invoices typically include customary adjustments for the resolution of price variability related to prior shipments, such as coal quality thresholds. Payments are generally received within thirty days of invoicing. |
| Inventories | Inventories Coal is reported as inventory at the point in time the coal is extracted from the mine. Raw coal represents coal stockpiles that may be sold in current condition or may be further processed prior to shipment to a customer. Saleable coal represents coal stockpiles which require no further processing prior to shipment to a customer. Coal inventory is valued at the lower of average cost or net realizable value. Coal inventory costs include labor, supplies, equipment (including depreciation thereto) and operating overhead and other related costs incurred at or on behalf of the mining location. Net realizable value considers the projected future sales price of the particular coal product, less applicable selling costs and, in the case of raw coal, estimated remaining processing costs. The valuation of coal inventory is subject to several additional estimates, including those related to ground and aerial surveys used to measure quantities and processing recovery rates. |
| Property, Plant, Equipment and Mine Development | Property, Plant, Equipment and Mine Development Property, plant, equipment and mine development are recorded at cost. Interest costs applicable to major asset additions are capitalized during the construction period. Capitalized interest for the year ended December 31, 2024 was $5.8 million. There was no capitalized interest in 2023 or 2022. Expenditures which extend the useful lives of existing plant and equipment assets are capitalized. Maintenance and repairs are charged to operating costs as incurred. Costs incurred to develop coal mines or to expand the capacity of operating mines are capitalized. Maintenance and repair costs incurred to maintain current production capacity at a mine are charged to operating costs as incurred. Costs to acquire computer hardware and the development and/or purchase of software for internal use are capitalized and depreciated over the estimated useful lives. Coal reserves and resources are recorded at cost, or at fair value in the case of nonmonetary exchanges of coal reserves and resources or business acquisitions. Depletion of coal reserves and resources and amortization of advance royalties are computed using the units-of-production method utilizing expected recoverable tons (as adjusted for recoverability factors) in the depletion base. Mine development costs are principally amortized over the estimated lives of the mine using the straight-line method. Depreciation of plant and equipment is computed using the straight-line method over the shorter of the asset’s estimated useful life or the life of the mine. At December 31, 2024, the maximum estimated remaining life for any of the Company’s mines was 29 years. As such, the estimated useful lives of the building and improvements and machinery and equipment asset categories range from 1 to 29 years. The estimated life of leasehold improvements is the shorter of useful life or remaining life of the lease. The Company leases coal reserves under agreements that require royalties to be paid as the coal is sold. Certain agreements also require minimum annual royalties to be paid regardless of the amount of coal mined during the year. Total royalty expense was $370.0 million, $448.3 million and $450.0 million for the years ended December 31, 2024, 2023 and 2022, respectively. A substantial amount of the coal mined by the Company is produced from mineral reserves leased from the owner. One of the major lessors is the U.S. government, from which the Company leases substantially all of the coal it mines in Wyoming under terms set by Congress and administered by the U.S. Bureau of Land Management. These leases are generally for an initial term of ten years but may be extended by diligent development and mining of the reserves until all economically recoverable reserves are depleted. The Company has met the diligent development requirements for substantially all of these federal leases either directly through production, by including the lease as a part of a logical mining unit with other leases upon which development has occurred or by paying an advance royalty in lieu of continued operations. Annual production on these federal leases must total at least 1.0% of the leased reserve or the original amount of coal in the entire logical mining unit in which the leased reserve resides. In addition, royalties are payable monthly at a rate of 12.5% of the gross realization from the sale of the coal mined using surface mining methods and at a rate of 8.0% of the gross realization for coal produced using underground mining methods. The remainder of the leased coal is generally leased from state governments, land holding companies and various individuals. The duration of these leases varies greatly. Typically, the lease terms are automatically extended as long as active mining continues. Royalty payments are generally based upon a specified rate per ton or a percentage of the gross realization from the sale of the coal. Mining and exploration in Australia is generally conducted under leases, licenses or permits granted by the relevant state government. Mining and exploration licenses and their associated environmental protection approvals (granted by the state government, and in some cases also the federal government) contain conditions relating to such matters as minimum annual expenditures, environmental compliance, protection of flora and fauna, restoration and rehabilitation. Royalties are paid to the state government as a percentage of the sales price (less certain allowable deductions in some cases). Generally, landowners do not own the mineral rights or have the ability to grant rights to mine those minerals. These rights are retained by the state government. Compensation is often payable to landowners, occupiers and Aboriginal traditional owners with residual native title rights and interests for the loss of access to the land from the proposed mining activities. The amount and type of compensation and the ability to proceed to grant of a mining tenement may be determined by agreement or court determination, as provided by law. |
| Leases | Leases |
| Equity Investments | Equity Investments The Company applies the equity method to investments when it has the ability to exercise significant influence over the operating and financial policies of the joint venture. Investments accounted for under the equity method are initially recorded at cost and any difference between the cost of the Company’s investment and the underlying equity in the net assets of the joint venture at the investment date is amortized over the lives of the related assets that gave rise to the difference. The Company’s pro-rata share of the operating results of joint ventures and basis difference amortization is reported in the consolidated statements of operations in “Income from equity affiliates.” Similarly, the Company’s pro-rata share of the cumulative foreign currency translation adjustment of its equity method investments whose functional currency is not the U.S. dollar is reported in the consolidated balance sheets as a component of “Accumulated other comprehensive income,” with periodic changes thereto reflected in the consolidated statements of comprehensive income. With respect to cash flows attributable to its equity investments, the Company applies the cumulative earnings approach, in which distributions received are considered returns on investment and are classified as cash inflows from operating activities unless the Company’s cumulative distributions received less distributions received in prior periods that were determined to be returns of investment exceed the cumulative equity in earnings recognized by the Company (as adjusted for amortization of basis differences). When such an excess occurs, current-period distributions up to this excess are considered returns of investment and are classified as cash inflows from investing activities. |
| Asset Retirement Obligations | Asset Retirement Obligations The Company’s asset retirement obligation (ARO) liabilities primarily consist of spending estimates for surface land reclamation and support facilities at both surface and underground mines in accordance with applicable reclamation laws and regulations in the U.S. and Australia as defined by each mining permit. Asset retirement obligations are determined for each mine using various estimates and assumptions including, among other items, estimates of disturbed acreage as determined from engineering data and estimates of future costs to reclaim the disturbed acreage. The Company estimates its ARO liabilities for final reclamation and mine closure based upon detailed engineering calculations of the amount and timing of the future cash spending for a third party to perform the required work. Spending estimates are escalated for inflation and then discounted at the credit-adjusted, risk-free rate. The Company records an ARO asset associated with the discounted liability for final reclamation and mine closure. The obligation and corresponding asset are recognized in the period in which the liability is incurred. The ARO asset is amortized on the units-of-production method over its expected life and the ARO liability is accreted to the projected spending date. As changes in estimates occur (such as mine plan revisions, changes in estimated costs or changes in timing of the performance of reclamation activities), the revisions to the obligation and asset are recognized at the appropriate credit-adjusted, risk-free rate. |
| Contingent Liabilities | Contingencies From time to time, the Company is subject to legal and environmental matters related to its continuing and discontinued operations and certain historical, non-coal producing operations. In connection with such matters, the Company is required to assess the likelihood of any adverse judgments or outcomes, as well as potential ranges of probable losses. A determination of the amount of reserves required for these matters is made after considerable analysis of each individual issue. The Company accrues for legal and environmental matters within “Operating costs and expenses” when it is probable that a liability has been incurred and the amount of the loss can be reasonably estimated. If a range of possible loss exists and no anticipated loss within the range is more likely than any other anticipated loss, the Company records the accrual at the low end of the range, in accordance with Accounting Standards Codification 450, “Contingencies.” The Company provides disclosure surrounding loss contingencies when it believes that it is at least reasonably possible that a material loss may be incurred or an exposure to loss in excess of amounts already accrued may exist. Adjustments to contingent liabilities are made when additional information becomes available that affects the amount of estimated loss, which information may include changes in facts and circumstances, changes in interpretations of law in the relevant courts, the results of new or updated environmental remediation cost studies and the ongoing consideration of trends in environmental remediation costs. Accrued contingent liabilities exclude claims against third parties and are not discounted. The current portion of these accruals is included in “Accounts payable and accrued expenses” and the long-term portion is included in “Other noncurrent liabilities” in the consolidated balance sheets. In general, legal fees related to environmental remediation and litigation are charged to expense. The Company includes the interest component of any litigation-related penalties within “Interest expense, net of capitalized interest” in the consolidated statements of operations. |
| Income Taxes | Income Taxes The Company recognizes deferred tax assets and liabilities for the temporary difference between the consolidated financial carrying amounts of existing assets and liabilities and their respective tax bases and consideration of operating loss and tax credit carryforwards. Deferred income taxes are measured using enacted rates in effect for the year in which temporary differences are expected to be recovered or settled. The impact on deferred tax assets and liabilities of a change in tax rates is recognized in the period that includes the enactment date. Valuation allowances are provided to reduce deferred tax assets to the amount that will be more likely than not realized. The Company makes judgments and estimates regarding the amount and timing of the reversal of taxable temporary differences, the impact of tax planning strategies and expected future taxable income. The Company recognizes the tax benefit from uncertain tax positions when it is more likely than not the tax position will be sustained upon examination by the taxing authorities based on the technical merits of the position. To the extent the Company’s assessment of such tax positions changes, the change in estimate will be recorded in the period in which the determination is made. Tax-related interest and penalties are classified as a component of income tax expense. |
| Postretirement Health Care and Life Insurance Benefits and Pension Plans | Postretirement Health Care and Life Insurance Benefits The Company accounts for postretirement benefits other than pensions by accruing the costs of benefits to be provided over the employees’ period of active service. These costs are determined on an actuarial basis. The Company’s consolidated balance sheets reflect the accumulated postretirement benefit obligations of its postretirement benefit plans. The Company accounts for changes in its postretirement benefit obligations as a settlement when an irrevocable action has been effected that relieves the Company of its actuarially-determined liability to individual plan participants and removes substantial risk surrounding the nature, amount and timing of the obligation’s funding and the assets used to effect the settlement. The Company records amounts attributable to actuarial valuation changes currently in earnings rather than recording such amounts within accumulated other comprehensive income and amortizing to expense over applicable time periods. See Note 13. “Postretirement Health Care and Life Insurance Benefits” for information related to postretirement benefits. Pension Plans The Company sponsors non-contributory defined benefit pension plans accounted for by accruing the cost to provide the benefits over the employees’ period of active service. These costs are determined on an actuarial basis. The Company’s consolidated balance sheets reflect the funded status of the defined benefit pension plans. The Company records amounts attributable to actuarial valuation changes currently in earnings rather than recording such amounts within accumulated other comprehensive income and amortizing to expense over applicable time periods. See Note 14. “Pension and Savings Plans” for information related to pension plans. |
| Restructuring Activities | Restructuring Activities From time to time, the Company initiates restructuring activities in connection with its repositioning efforts to appropriately align its cost structure or optimize its coal production relative to prevailing market conditions. Costs associated with restructuring actions can include the impact of early mine closures, voluntary and involuntary workforce reductions, office closures and other related activities. Costs associated with restructuring activities are recognized in the period incurred. Included as a component of “Restructuring charges” in the Company’s consolidated statements of operations for the years ended December 31, 2024, 2023 and 2022 were aggregate restructuring charges of $4.4 million, $3.3 million and $2.9 million, respectively, primarily associated with voluntary and involuntary workforce reductions. As of December 31, 2024, a $3.4 million accrual for restructuring charges remained in “Accounts payable and accrued expenses,” which is expected to be paid during 2025. |
| Derivatives | Derivatives The Company recognizes at fair value all contracts meeting the definition of a derivative as assets or liabilities in the consolidated balance sheets, with the exception of certain sales contracts for which the Company has elected to apply a normal purchases and normal sales exception. With respect to derivatives used in hedging activities, the Company assesses at hedge inception whether such derivatives are highly effective at offsetting the changes in the anticipated exposure of the hedged item. The change in the fair value of derivatives designated as a cash flow hedge is recorded in “Accumulated other comprehensive income” in the consolidated balance sheets until the hedged transaction impacts reported earnings, at which time any gain or loss is reclassified to earnings. If the hedge ceases to qualify for hedge accounting, the Company prospectively recognizes changes in the fair value of the instrument in earnings in the period of the change. Gains or losses from derivative financial instruments designated as fair value hedges are recognized immediately in earnings, along with the offsetting gain or loss related to the underlying hedged item. The Company’s asset and liability derivative positions are offset on a counterparty-by-counterparty basis if the contractual agreement provides for the net settlement of contracts with the counterparty in the event of default or termination of any one contract. Non-derivative contracts and derivative contracts for which the Company has elected to apply the normal purchases and normal sales exception are accounted for on an accrual basis. |
| Business Combinations and Asset Acquisitions | Business Combinations The Company accounts for business combinations using the acquisition method of accounting. The acquisition method requires the Company to determine the fair value of all acquired assets, including identifiable intangible assets and all assumed liabilities. The total cost of acquisitions is allocated to the underlying identifiable net assets, based on their respective estimated fair values. Determining the fair value of assets acquired and liabilities assumed requires management’s judgment and the utilization of independent valuation experts, and often involves the use of significant estimates and assumptions, including assumptions with respect to future cash inflows and outflows, discount rates and asset lives, among other items. Asset Acquisitions The Company recognizes the obligation for contingent consideration in asset acquisitions as an adjustment to the cost basis of the assets acquired if and when the contingency is resolved and the consideration is paid or becomes payable. |
| Impairment of Long-Lived Assets | Impairment of Long-Lived Assets The Company evaluates its long-lived assets held and used in operations for impairment as events and changes in circumstances indicate that the carrying amount of such assets might not be recoverable. Factors that would indicate potential impairment to be present include, but are not limited to, a sustained history of operating or cash flow losses, an unfavorable change in earnings and cash flow outlook, prolonged adverse industry or economic trends and a significant adverse change in the extent or manner in which a long-lived asset is being used or in its physical condition. The Company generally does not view short-term declines in thermal and metallurgical coal prices as an indicator of impairment for conducting impairment tests because of historic price volatility. However, the Company generally views a sustained trend of depressed coal pricing (for example, over periods exceeding one year) as a potential indicator of impairment. Because of the volatile and cyclical nature of coal prices and demand, it is reasonably possible that coal prices may decrease and/or fail to improve in the near term, which, absent sufficient mitigation such as an offsetting reduction in the Company’s operating costs, may result in the need for future adjustments to the carrying value of its long-lived mining assets and mining-related investments. Assets are grouped at the lowest level for which there are identifiable cash flows that are largely independent of the cash flows of other groups of assets. For its active mining operations, the Company generally groups such assets at the mine level, or the mining complex level for mines that share infrastructure. For its development and exploration properties and portfolio of surface land and coal reserve and resource holdings, the Company considers several factors to determine whether to evaluate those assets individually or on a grouped basis for purposes of impairment testing. Such factors include geographic proximity to one another, the expectation of shared infrastructure upon development based on future mining plans and whether it would be most advantageous to bundle such assets in the event of sale to a third party. When indicators of impairment are present, the Company evaluates its long-lived assets for recoverability by comparing the estimated undiscounted cash flows expected to be generated by those assets under various assumptions to their carrying amounts. If such undiscounted cash flows indicate that the carrying value of the asset group is not recoverable, impairment losses are measured by comparing the estimated fair value of the asset group to its carrying amount. As quoted market prices are unavailable for the Company’s individual mining operations, fair value is determined through the use of an expected present value technique based on the income approach, except for non-strategic coal reserves, coal resources, surface lands and undeveloped coal properties excluded from the Company’s long-range mine planning. In those cases, a market approach is utilized based on the most comparable market multiples available. The estimated future cash flows and underlying assumptions used to assess recoverability and, if necessary, measure the fair value of the Company’s long-lived mining assets are derived from those developed in connection with the Company’s planning and budgeting process. The Company believes its assumptions to be consistent with those a market participant would use for valuation purposes. The most critical assumptions underlying the Company’s projections and fair value estimates include those surrounding future tons sold, coal prices for unpriced coal, production costs (including costs for labor, commodity supplies and contractors), transportation costs, foreign currency exchange rates and a risk-adjusted, cost of capital (all of which generally constitute unobservable Level 3 inputs under the fair value hierarchy), in addition to market multiples for non-strategic coal reserves, coal resources, surface lands and undeveloped coal properties excluded from the Company’s long-range mine planning (which generally constitute Level 2 inputs under the fair value hierarchy). |
| Fair Value | Fair Value |
| Foreign Currency | Foreign Currency Functional currency is determined by the primary economic environment in which an entity operates, which for the Company’s foreign operations is generally the U.S. dollar because sales prices in international coal markets and the Company’s sources of financing for those operations are denominated in that currency. Accordingly, substantially all of the Company’s consolidated foreign subsidiaries utilize the U.S. dollar as their functional currency. Monetary assets and liabilities are remeasured at year-end exchange rates while non-monetary items are remeasured at historical rates. Income and expense accounts are remeasured at the average rates in effect during the year, except for those expenses related to balance sheet amounts that are remeasured at historical exchange rates. Gains and losses from foreign currency remeasurement related to tax balances are included as a component of “Income tax provision (benefit),” while all other remeasurement gains and losses are included in “Operating costs and expenses” in the consolidated statements of operations. The total impact of foreign currency remeasurement on the consolidated statements of operations was a net loss of $32.3 million for the year ended December 31, 2024 and net gains of $5.3 million and $2.7 million for the years ended December 31, 2023 and 2022, respectively. The Company owns a 50% equity interest in Middlemount Coal Pty Ltd. (Middlemount), which owns the Middlemount Mine in Queensland, Australia. Middlemount utilizes the Australian dollar as its functional currency. Accordingly, the assets and liabilities of that equity investee are translated to U.S. dollars at the year-end exchange rate and income and expense accounts are translated at the average rate in effect during the year. The Company’s pro-rata share of the translation gains and losses of the equity investee are recorded as a component of “Accumulated other comprehensive income” in the consolidated balance sheets. Australian dollar denominated stockholder loans to the Middlemount Mine, which are long term in nature, are considered part of the Company’s net investment in that operation. Accordingly, foreign currency gains or losses on those loans are recorded as a component of foreign currency translation adjustment. The Company recorded a net loss from foreign currency translation of $4.3 million for year ended December 31, 2024, a net gain of $0.9 million for the year ended December 31, 2023 and a net loss of $1.6 million for the year ended December 31, 2022. |
| Share-Based Compensation | Share-Based Compensation The Company accounts for share-based compensation at the grant date fair value of awards and recognizes the related expense over the service period of the awards. See Note 16. “Share-Based Compensation” for information related to share-based compensation. |
| Exploration and Drilling Costs | Exploration and Drilling Costs Exploration expenditures are charged to operating costs as incurred, including costs related to drilling and study costs incurred to convert or upgrade mineral resources to reserves. |
| Advance Stripping Costs | Advance Stripping Costs Pre-production. At existing surface operations, additional pits may be added to increase production capacity in order to meet customer requirements. These expansions may require significant capital to purchase additional equipment, expand the workforce, build or improve existing haul roads and create the initial pre-production box cut to remove overburden (that is, advance stripping costs) for new pits at existing operations. If these pits operate in a separate and distinct area of the mine, the costs associated with initially uncovering coal (that is, advance stripping costs incurred for the initial box cuts) for production are capitalized and amortized over the life of the developed pit consistent with coal industry practices. Post-production. Advance stripping costs related to post-production are expensed as incurred. Where new pits are routinely developed as part of a contiguous mining sequence, the Company expenses such costs as incurred. The development of a contiguous pit typically reflects the planned progression of an existing pit, thus maintaining production levels from the same mining area utilizing the same employee group and equipment. |
| Use of Estimates in the Preparation of the Consolidated Financial Statements | Use of Estimates in the Preparation of the Consolidated Financial Statements These consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States (U.S. GAAP). In doing so, estimates and assumptions are made that affect the amounts reported in the consolidated financial statements and accompanying notes. These estimates are based on historical experience and on various other assumptions deemed reasonable under the circumstances, the results of which form the basis for making judgments about the carrying amounts of assets and liabilities that are not readily apparent from other sources. The Company’s actual results may differ materially from these estimates. Significant estimates inherent in the preparation of these consolidated financial statements include, but are not limited to, accounting for sales and cost recognition, postretirement benefit plans, environmental receivables and liabilities, asset retirement obligations, evaluation of long-lived assets for impairment, income taxes including deferred tax assets, fair value measurements and contingencies. |
| Corporate Hedging - Coal Trading | The Company’s risk management function, which is independent of the Company’s coal trading function, is responsible for valuation policies and procedures, with oversight from executive management. The fair value of the Company’s coal derivative assets and liabilities reflects adjustments for credit risk. The Company’s exposure to credit risk is substantially with electric utilities, energy marketers, steel producers and nonfinancial trading houses. |
| Fair Value Transfer, Policy | The Company’s policy is to value all transfers between levels using the beginning of period valuation. |
| Description of business | Description of Business The Company is engaged in the mining of thermal coal for sale primarily to electric utilities and industrial facilities and metallurgical coal for sale to steel producers. The Company’s mining operations are located in the United States (U.S.) and Australia, including an equity-affiliate mining operation in Australia. The Company’s other commercial activities include trading and brokerage activities, managing its coal reserves and resources and real estate holdings and supporting the development of clean coal technologies. On November 21, 2024, Peabody entered into a partnership with an unrelated renewable energy company, to advance renewable energy projects by repurposing reclaimed land previously used for mining, including certain reclaimed mining land held by the Company. |
