VARIABLE INTEREST ENTITIES - Summary (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
Dec. 31, 2025 |
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| Variable Interest Entity [Line Items] | |||||
| Net electric plant | $ 3,341,609 | $ 3,341,609 | $ 3,305,524 | ||
| Noncontrolling interest | 129,358 | 129,358 | 130,132 | ||
| Long-term debt | 2,859,974 | 2,859,974 | 3,093,216 | ||
| Accrued interest | 41,912 | 41,912 | 22,632 | ||
| Interest | 44,436 | $ 47,124 | 132,818 | $ 127,327 | |
| Variable Interest Entity, Primary Beneficiary | Reportable Legal Entities | |||||
| Variable Interest Entity [Line Items] | |||||
| Net electric plant | 605,335 | 605,335 | 635,777 | ||
| Noncontrolling interest | 129,358 | 129,358 | 130,132 | ||
| Long-term debt | 171,657 | 171,657 | 172,158 | ||
| Accrued interest | 1,999 | 1,999 | $ 4,997 | ||
| Depreciation, amortization and depletion | 10,147 | 10,147 | 30,442 | 30,442 | |
| Interest | $ 2,828 | $ 2,839 | $ 8,493 | $ 8,525 | |
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- Definition Amount of the cost of borrowed funds, net of capitalized interest costs, accounted for as interest expense No definition available.
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- Definition The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of equity (deficit) attributable to noncontrolling interest. Excludes temporary equity. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Period end amount of total net PPE. No definition available.
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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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