Asset Acquisition, Consideration Transferred, Excluding Transaction Cost

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- Definition

Contingent royalty

+ References

No definition available.

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- Definition

Deductible amount

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No definition available.

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- Definition

Loss limits on insurance claim, amount

+ References

No definition available.

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- Definition

[Line Items] for Other Commercial Events [Table]

+ References

No definition available.

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- Definition

Amount of transaction cost incurred as part of consideration transferred in asset acquisition.

+ References

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-Name Accounting Standards Codification
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- Definition

The fair value of assets acquired in noncash investing or financing activities.

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- Definition

The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.

+ References

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-Topic 220
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The value of an asset or business acquired in a noncash (or part noncash) acquisition. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

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- Definition

Amount of cash inflow for proceeds from settlement of insurance claim, classified as investing activities. Excludes insurance settlement classified as operating activities.

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- Definition

Amount remaining authorized for purchase of share under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership.

+ References

No definition available.

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Other Events Narrative (Details) - USD ($)		1 Months Ended	3 Months Ended		9 Months Ended
Other Events Narrative (Details) - USD ($)	Apr. 16, 2024	Oct. 31, 2023	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Other Commercial Events [Line Items]
Shoal Creek insurance recovery			$ 0	$ 0	$ 0	$ 109,500,000
Proceeds from Insurance Settlement, Investing Activities					0	10,900,000
Loss Contingency, Receivable				$ 5,700,000		5,700,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount			$ 469,600,000		$ 469,600,000
Wards Well coal deposit
Other Commercial Events [Line Items]
Fair Value of Assets Acquired	$ 153,400,000
Asset Acquisition, Consideration Transferred, Excluding Transaction Cost	134,400,000
Asset Acquisition, Consideration Transferred, Transaction Cost	9,400,000
Noncash or Part Noncash Acquisition, Value of Assets Acquired	9,600,000
Contingent royalty	$ 200,000,000
Shoal Creek Mine
Other Commercial Events [Line Items]
Business interruption and property loss limits on insurance claim, amount		$ 125,000,000
Deductible amount		$ 50,000,000
Shoal Creek insurance recovery						$ 103,800,000