Nuclear Decommissioning Trust Funds - Schedule of Maturities for Available-for-Sale Debt Securities (Details) - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
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| Investments, Debt and Equity Securities [Abstract] | ||
| Maturities within one year | $ 23 | $ 23 |
| Maturities within two to five years | 253 | 233 |
| Maturities thereafter | 628 | 521 |
| Debt securities, fair value | $ 904 | $ 777 |
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- Definition Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, After Year Five No definition available.
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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