MATERIALS, SUPPLIES, AND INVENTORIES (Details) - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Energy Related Inventory | ||
| Materials and supplies | $ 428.9 | $ 416.4 |
| Natural gas in storage | 357.5 | 292.5 |
| Fossil fuel | 78.8 | 94.5 |
| Total | 865.2 | $ 803.4 |
| LIFO Method Related Items | ||
| LIFO liquidation credit | $ 0.0 |
| X | ||||||||||
- Definition Carrying amount as of the balance sheet date of merchandise, goods, commodities, or supplies relating to a source of usable power held for future sale or future use in manufacturing or production process. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition Carrying amount as of the balance sheet date of natural gas in storage, which is a mixture of gases (liquefied or otherwise), used for fuel and manufacturing purposes, which is ready for sale. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of fossil fuel included in inventory classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The excess of replacement or current cost over the stated LIFO (last in first out) inventory value when the LIFO inventory method is utilized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Aggregated amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed. This amount is net of valuation reserves and adjustments. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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