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Common Equity (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2023
Common Equity [Line Items] |  |  |  |  |
Proceeds from issuance of common stock, net | $ 125 | $ 6 | $ 201 | $ 19 |
At The Market Offering Program [Member] |  |  |  |  |
Common Equity [Line Items] |  |  |  |  |
Common stock issued during period, At-the-market offering program (in shares) |  |  | 3,569,937 |  |
Proceeds from issuance of common stock, net |  |  | $ 183 |  |
Fees and commissions from issuance of common stock |  |  | $ 2 |  |
At The Market Offering Program [Member] | Forecast [Member] |  |  |  |  |
Common Equity [Line Items] |  |  |  |  |
Maximum aggregate gross sales price of common stock that can be offered and sold |  |  |  |  | $ 225

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