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Common Equity (Common Share Activity) (Details) - shares | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Common Stock Oustanding [Roll Forward] |  |  |
Shares outstanding, January 1 (in shares) | 249,868,415 | 245,022,800 | 236,063,279
Common stock issued during the period, Shareowner Direct Plan (in shares) | 492,565 | 472,283 | 501,808
Common stock issued during the period, Equity-based compensation plans (in shares) | 113,549 | 98,205 | 101,478
Common stock issued during the period, Other (in shares) | 0 | 0 | (2,738)
Shares outstanding, December 31 (in shares) | 250,474,529 | 249,868,415 | 245,022,800
Equity Forward Agreements [Member] |  |  |
Common Stock Oustanding [Roll Forward] |  |  |
Common stock issued during the period (in shares) | 0 | 4,275,127 | 8,358,973

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