Unconsolidated Subsidiaries (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
Jun. 30, 2025 |
Jun. 30, 2024 |
Dec. 31, 2024 |
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| Variable Interest Entity [Line Items] | |||||
| Variable interest entity, reporting entity involvement, maximum risk of loss | $ 4,800 | $ 4,800 | $ 5,500 | ||
| Earnings of unconsolidated operations | 13,138 | $ 13,592 | 29,124 | $ 26,899 | |
| Utility Coal Mining and Contract Mining Member | |||||
| Variable Interest Entity [Line Items] | |||||
| Earnings of unconsolidated operations | $ 12,900 | $ 13,500 | $ 28,300 | $ 26,800 | |
| Unconsolidated Subsidiaries | |||||
| Variable Interest Entity [Line Items] | |||||
| Ownership percentage | 100.00% | 100.00% | |||
| Income from equity method investee | $ 16,093 | $ 16,093 | 14,137 | ||
| Other Noncurrent Assets | |||||
| Variable Interest Entity [Line Items] | |||||
| Income from equity method investee | $ 16,100 | $ 16,100 | $ 14,100 | ||
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- Definition This item represents the entity's proportionate share for the period of the pre-tax earnings of the unconsolidated mines to which the equity method of accounting is applied. Income tax amounts are included in the income tax provision line. No definition available.
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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