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Nuclear Decommissioning Trust Funds (Tables) | 6 Months Ended
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Jun. 30, 2025
Investments, Debt and Equity Securities [Abstract] |
Schedule of Unrealized Gain (Loss) on Nuclear Decommissioning Trust Funds |
|  | June 30, 2025 |  | December 31, 2024
|  | Amortized Cost |  | Unrealized Gains |  | Unrealized Losses |  | Fair Value |  | Amortized Cost |  | Unrealized Gains |  | Unrealized Losses |  | Fair Value
Cash equivalents |  | $ | 14 |  |  | $ | — |  |  | $ | — |  |  | $ | 14 |  |  | $ | 3 |  |  | $ | — |  |  | $ | — |  |  | $ | 3 |
Equity securities |  | 513 |  |  | 680 |  |  | (47) |  |  | 1,146 |  |  | 509 |  |  | 651 |  |  | (55) |  |  | 1,105 |
Debt securities |  | 615 |  |  | 7 |  |  | (5) |  |  | 617 |  |  | 615 |  |  | 3 |  |  | (7) |  |  | 611 |
Receivables (payables), net |  | 13 |  |  | — |  |  | — |  |  | 13 |  |  | 5 |  |  | — |  |  | — |  |  | 5 |
NDT Funds |  | $ | 1,155 |  |  | $ | 687 |  |  | $ | (52) |  |  | $ | 1,790 |  |  | $ | 1,132 |  |  | $ | 654 |  |  | $ | (62) |  |  | $ | 1,724 |
Schedule of Available-for-Sale Debt Securities With Unrealized Losses | The aggregate fair value of available-for-sale debt securities with unrealized losses as of June 30, 2025 was:
|  | Fair Value |  | Unrealized Losses
Corporate debt securities |  | $ | 32 |  |  | $ | (1) |
Municipal debt securities |  | 71 |  | (2) |
U.S. Government debt securities |  | 48 |  | (1) |
Debt securities in unrealized loss position |  | $ | 151 |  |  | $ | (5) |
Schedule of Maturities for Available-for-Sale Debt Securities | The contractual maturities for available-for-sale debt securities presented on the Consolidated Balance Sheets were:
|  | June 30, 2025 |  | December 31, 2024
Maturities within one year |  | $ | 66 |  |  | $ | 82 |
Maturities within two to five years |  | 196 |  |  | 220 |
Maturities thereafter |  | 356 |  |  | 309 |
Debt securities, fair value |  | $ | 617 |  |  | $ | 611 |
Schedule of Sales Proceeds, Gains, and Losses for Available-for-Sale Debt Securities | The sales proceeds, gains, and losses for available-for-sale debt securities for the periods were:
|  | Three Months Ended June 30, |  | Six Months Ended June 30, |  |  |
|  | 2025 |  | 2024 |  | 2025 |  | 2024 |  |  |  |  |
Sales proceeds of NDT funds investments (a) |  | $ | 592 |  |  | $ | 535 |  |  | $ | 1,168 |  |  | $ | 1,034 |  |  |  |  |  |
Gross realized gains |  | 4 |  |  | 2 |  |  | 7 |  |  | 5 |  |  |  |  |  |
Gross realized losses |  | (3) |  |  | (3) |  |  | (5) |  |  | (6) |  |  |  |  |  |
__________________ (a)Sales proceeds are used to pay income taxes and trust management fees. Remaining proceeds are reinvested in the NDT.

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