Segment Information - Schedule of Segment Information (Detail) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
Jun. 30, 2025 |
Jun. 30, 2024 |
Dec. 31, 2024 |
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| Segment Reporting Information [Line Items] | |||||
| Total revenues | $ 839 | $ 672 | $ 1,488 | $ 1,220 | |
| Fuel | 120 | 131 | 243 | 264 | |
| Purchased power | 68 | 35 | 106 | 43 | |
| Operations & maintenance, excluding FPSC-approved regulatory deferrals | 100 | 96 | 197 | 191 | |
| Operations & maintenance related to FPSC-approved regulatory deferrals | 106 | 46 | 151 | 85 | |
| Depreciation and amortization | 124 | 113 | 246 | 225 | |
| Total interest charges | 52 | 47 | 104 | 96 | |
| Other segment items | 48 | 50 | 88 | 91 | |
| Provision for income taxes | 33 | 18 | 51 | 26 | |
| Net Income (Loss) | 188 | 136 | 302 | 199 | |
| Capital expenditures | 459 | $ 339 | 768 | $ 607 | |
| Total assets | $ 13,730 | $ 13,730 | $ 13,107 | ||
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- Definition Operations and maintenance excluding fpsc approved regulatory deferrals. No definition available.
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- Definition Operations and maintenance related to fpsc approved regulatory deferrals. No definition available.
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- Definition Amount of asset recognized for present right to economic benefit. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fuel costs incurred that are directly related to goods produced and sold and services rendered during the reporting period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of interest expense classified as operating and nonoperating. Includes, but is not limited to, cost of borrowing accounted for as interest expense. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of revenue and income classified as other. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). Reference 1: http://www.xbrl.org/2003/role/exampleRef
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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. No definition available.
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- Definition Amount of operating expense for purchased power of regulated operation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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