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Nuclear Decommissioning Trust Funds - Schedule of Unrealized Gain (Loss) on Nuclear Decommissioning Trust Funds (Details) - USD ($) $ in Millions | Jun. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items] |  |
Cash equivalents, Amortized Cost | $ 122 | $ 328
Cash equivalents, Fair Value | 14 | 3
Fair value of equity | 513 | 509
Equity securities, Unrealized Gains | 680 | 651
Equity securities, Unrealized Losses | (47) | (55)
Equity securities, Fair Value | 1,146 | 1,105
Debt securities, Amortized Cost | 615 | 615
Debt securities, Unrealized Gains | 7 | 3
Debt securities, Unrealized Losses | (5) | (7)
Debt securities | 617 | 611
Receivables (payables), net, Amortized Cost | 13 | 5
Receivables (payables), net, Fair Value | 13 | 5
Amortized Cost | 1,155 | 1,132
Unrealized Gains | 687 | 654
Unrealized Losses | (52) | (62)
NDT funds | 1,790 | 1,724
Cash equivalents |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items] |  |
Cash equivalents, Amortized Cost | 14 | 3
Cash equivalents, Fair Value | $ 14 | $ 3

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- Definition The fair value of investments held in a trust fund to pay for the costs of decontaminating and decommissioning facilities, whether such amount is presented as a separate caption or as a parenthetical disclosure on the balance sheet. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 410 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481850/410-20-50-1 + Details
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