Contract Obligations (Summary of Contract Obligations) (Details) $ in Thousands, $ in Millions |
Dec. 31, 2025
AUD ($)
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Dec. 31, 2025
USD ($)
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Dec. 31, 2024
USD ($)
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|---|---|---|---|
| Debt Instrument [Line Items] | |||
| Short-term | $ 22,445 | $ 37,090 | |
| Long-term | 522,968 | 312,822 | |
| Total | 545,413 | 349,912 | |
| Coal Leases Contract Liability [Member] | |||
| Debt Instrument [Line Items] | |||
| Short-term | 843 | 843 | |
| Long-term | 18,818 | 19,156 | |
| Total | 19,661 | 19,999 | |
| Stanwell Prepaid Coal Supply Liability [Member] | |||
| Debt Instrument [Line Items] | |||
| Contract liability, short-term | 0 | ||
| Contract liability, long-term | $ 231.6 | 155,027 | |
| Contract liability, Total | 155,027 | ||
| Stanwell Below Market Coal Supply Agreement [Member] | |||
| Debt Instrument [Line Items] | |||
| Short-term | 21,602 | 36,247 | |
| Long-term | 2,355 | 8,616 | |
| Total | 23,957 | 44,863 | |
| Stanwell Deferred Consideration Liability [Member] | |||
| Debt Instrument [Line Items] | |||
| Deferred consideration liability, short-term | 0 | 0 | |
| Deferred consideration liability, long-term | 346,768 | 285,050 | |
| Deferred consideration liability, Total | $ 346,768 | $ 285,050 |
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- Definition Contract Liability, non-current No definition available.
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- Definition Contract Liability, Current No definition available.
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- Definition Contract Liability, Current And Noncurrent No definition available.
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- Definition Current portion of non-market contracts. No definition available.
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- Definition Non-Current portion of non-market contracts. No definition available.
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- Definition Amount of contractual obligation, including, but not limited to, long-term debt, lease obligation, purchase obligation, and other commitments. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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- Definition Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable beyond one year (or the operating cycle, if longer). No definition available.
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- Definition Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable within one year (or the operating cycle, if longer). Represents currently earned compensation under compensation arrangements that is not actually paid until a later date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date. No definition available.
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