v3.25.4

Federal Coal Lease Obligations - Narrative (Details) - USD ($) |  | 12 Months Ended
--- | --- | ---
Nov. 25, 2025 | Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Leases [Abstract] |  |  |  |
Lease obligation | $ 46,800 |  |  |
Payment for federal coal lease | $ 9,400,000 | $ 9,363,000 | $ 0 | $ 0
Lease installment due, year one |  | 9,400,000 |  |
Lease installment due, year two |  | 9,400,000 |  |
Lease installment due, year three |  | 9,400,000 |  |
Lease installment due, year four |  | 9,400,000 |  |
Short-term federal coal lease obligations |  | 8,844,000 | 0 |
Long-term federal coal lease obligations |  | $ 23,679,000 | $ 0 |

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- Definition Federal coal lease liability current. + References No definition available. + Details
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- Definition Federal coal lease liability noncurrent. + References No definition available. + Details
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- References No definition available. + Details
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- Definition The cash outflow from the acquisition of a mineral right which is the right to extract a mineral from the earth or to receive payment, in the form of royalty, for the extraction of minerals. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 13 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-13 + Details
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- Definition Amount of the recorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 440 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482648/440-10-50-6 + Details
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- Definition Amount of recorded unconditional purchase obligation to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 440 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482648/440-10-50-6 + Details
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- Definition Amount of recorded unconditional purchase obligation to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 440 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482648/440-10-50-6 + Details
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- Definition Amount of recorded unconditional purchase obligation to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 440 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482648/440-10-50-6 + Details
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- Definition Amount of recorded unconditional purchase obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 440 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482648/440-10-50-6 + Details
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