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Common Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Schedule of Common Equity [Line Items] |  |  |
Shares available for issuance under the 2020 OIP, Shareowner Direct Plan and 401(k) Savings Plan (in shares) | 14,000,000 |  |
Proceeds from issuance of common stock, net | $ 28 | $ 247 | $ 390
Equity Forward Agreements [Member] |  |  |
Schedule of Common Equity [Line Items] |  |  |
Common stock issued during the period (in shares) | 0 | 4,275,127 | 8,358,973
Proceeds from issuance of common stock, net |  | $ 222 | $ 366
Initial forward sale price (in dollars per share) |  | $ 51.98 | $ 43.75

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