The amount of gain that could be realized upon the resolution of a contingency.

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The amount of expenses relating to loss contingency receivable, during the period.

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The number of raw coal storage silos.

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The number of raw coal storage silos that experienced partial structure failure.

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No definition available.

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The percent of plant capacity restored after partial structural failure.

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No definition available.

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- Definition

Number of multi-year contracts undertake-or-pay arrangements of purchase commitments.

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No definition available.

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- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

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The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Amount awarded from other party in judgment or settlement of litigation.

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No definition available.

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The minimum amount the entity agreed to spend under the long-term purchase commitment.

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No definition available.

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Amount of loss contingency liability.

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Amount of damages awarded to the plaintiff in the legal matter.

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Amount of receivable related to a loss contingency accrual. For example, an insurance recovery receivable.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of additions to receivables pertaining to a loss contingency.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

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Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations.

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- Definition

The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

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Amount of expense related to royalty payments under a contractual arrangement such as payment for mineral and drilling rights and use of technology or intellectual property.

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Commitments and Contingencies (Details)						1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
Commitments and Contingencies (Details)	Jul. 20, 2023 USD ($)	Mar. 04, 2022 USD ($)	Jul. 16, 2021 USD ($)	Jul. 15, 2021 USD ($)	Nov. 05, 2018	Feb. 29, 2024 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
Commitments and Contingencies [Line Items]
Royalty expense							$ 4,500,000	$ 6,400,000	$ 17,300,000	$ 19,500,000
Accrued amount							0		0
Payments to acquire property, plant, and equipment						$ 3,000,000
Number of raw coal storage silos, failure					1
Number of raw coal storage silos					3
Percentage of structural failure					80.00%
Compensatory damages	$ 7,700,000	$ 1,800,000	$ 25,000,000	$ 7,700,000
Award to cover inconvenience and aggravation	$ 25,000,000
Gain recorded from contingency											$ 7,800,000
Insurance proceeds related to property, plant, and equipment											$ 2,000,000
Additional loss recovery asset									100,000
Total loss recovery asset							4,700,000		4,700,000
Corresponding reduction									100,000
Surety Bond [Member]
Commitments and Contingencies [Line Items]
Asset retirement obligation							34,700,000		34,700,000
Environmental Issue [Member]
Commitments and Contingencies [Line Items]
Environmental liabilities							0		0
Take-or-Pay Purchase Commitments [Member]
Commitments and Contingencies [Line Items]
Total commitment									$ 23,400,000
Number of multi-year Contract									2
Take or Pay Purchase Commitments, Multi Year Contract, One [Member]
Commitments and Contingencies [Line Items]
Commitment							11,300,000		$ 11,300,000
Multi-Year Contract, Two [Member]
Commitments and Contingencies [Line Items]
Commitment							11,800,000		11,800,000
Environmental Restoration Costs [Member]
Commitments and Contingencies [Line Items]
Regulatory Liability							$ 0		$ 0