Select Balance Sheet Information - Schedule of Property, Plant and Equipment (Details) - USD ($) $ in Thousands |
Jun. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Electric Plant | ||
| Electric Plant in Service | $ 3,461,933 | $ 3,370,677 |
| Construction Work in Progress | 400,844 | 233,978 |
| Total Gross Electric Plant | 3,862,777 | 3,604,655 |
| Less Accumulated Depreciation | 897,871 | 899,401 |
| Net Electric Plant | 2,964,906 | 2,705,254 |
| Nonelectric Property, Plant and Equipment | ||
| Nonelectric Property, Plant and Equipment | 412,845 | 404,922 |
| Construction Work in Progress | 14,989 | 12,389 |
| Total Gross Nonelectric Property, Plant and Equipment | 427,834 | 417,311 |
| Less Accumulated Depreciation | 254,310 | 245,880 |
| Net Nonelectric Property, Plant and Equipment | 173,524 | 171,431 |
| Total Net Property, Plant and Equipment | $ 3,138,430 | $ 2,876,685 |
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- Definition Property, Plant and Equipment, Construction Work in Progress No definition available.
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- Definition Property, Plant and Equipment, Net Including Public Utilities No definition available.
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- Definition Property, Plant and Equipment, Nonelectric No definition available.
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- Definition Public Utilities, Property, Plant and Equipment, Gross No definition available.
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- Definition Amount of accumulated depreciation, depletion, and amortization of property, plant, and equipment. Includes, but is not limited to, land and land improvement; building; machinery and equipment; furniture and fixture; and work of art, historical treasure, or similar asset classified as collection. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount, before accumulated depreciation, depletion, and amortization, of property, plant, and equipment. Includes, but is not limited to, land and land improvement; building; machinery and equipment; furniture and fixture; and work of art, historical treasure, or similar asset classified as collection. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after accumulated depreciation, depletion, and amortization, of property, plant, and equipment. Includes, but is not limited to, land and land improvement; building; machinery and equipment; furniture and fixture; and work of art, historical treasure, or similar asset classified as collection. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Period end book value of accumulated depreciation on property, plant and equipment (PPE) that is owned by the regulated operations of the public utility. No definition available.
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- Definition Period end amount of construction work in progress in public utility. No definition available.
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- Definition Period end amount of total net PPE. No definition available.
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- References No definition available.
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- Definition Period end amount of total gross PPE. No definition available.
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