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Common Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 5 Months Ended | 9 Months Ended | 44 Months Ended
--- | --- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2028
Common Equity [Line Items] |  |  |  |  |  |
Proceeds from issuance of common stock, net | $ 6 | $ 6 |  | $ 18 | $ 18 |
At-The-Market Offering Program 2025-2028 [Member] |  |  |  |  |  |
Common Equity [Line Items] |  |  |  |  |  |
Forward contract, total shares borrowed and sold (in shares) | 7,851,080 |  |  | 10,764,103 |  |
Aggregate gross sales price of common stock borrowed or sold | $ 508 |  |  | $ 686 |  |
Fees and commissions from issuance of common stock | $ 4 |  |  | $ 5 |  |
Forward contract, weighted-average forward price, net of commissions (in dollars per share) |  |  | $ 63.46 |  |  |
Forward contract, shares that could have settled under outstanding forward sale agreements with physical delivery (in shares) | 10,764,103 |  | 10,764,103 | 10,764,103 |  |
Forward contract, net cash proceeds upon settlement | $ 683 |  | $ 683 | $ 683 |  |
Shares included in diluted earnings per share (in shares) |  |  |  | 199,923 |  |
At-The-Market Offering Program 2025-2028 [Member] | Forecast [Member] |  |  |  |  |  |
Common Equity [Line Items] |  |  |  |  |  |
Proceeds from issuance of common stock, net |  |  |  |  |  | $ 1,300

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