OTHER DEFERRED CREDITS AND OTHER LIABILITIES - Summary (Details) - USD ($) $ in Thousands |
Sep. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Deferred Credits and Other Liabilities [Abstract] | ||
| Transmission easements | $ 14,976 | $ 15,373 |
| OATT deposits | 24,929 | 32,129 |
| Financial liabilities - reclamation | 10,468 | 10,837 |
| Customer deposits | 6,860 | 16,517 |
| Contract liabilities (unearned revenue) - noncurrent | 2,807 | 3,182 |
| Lease liabilities - noncurrent | 6,038 | 6,473 |
| Other | 7,466 | 7,369 |
| Total other deferred credits and other liabilities | $ 73,544 | $ 91,880 |
| X | ||||||||||
- Definition Amounts received from customers that are expected to be returned upon satisfactory contract completion. No definition available.
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- Definition Present value of easement right of way payments due recorded. No definition available.
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- Definition Lease, Liability, Noncurrent No definition available.
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- Definition Total carrying amount as of the balance sheet date of other deferred credits and other obligations not separately disclosed in the balance sheet. No definition available.
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- Definition Transmission Deposits No definition available.
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- Definition Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable after twelve months or beyond the next operating cycle if longer. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount of liabilities classified as other. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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