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Common Equity (Common Share Activity) (Details) | 9 Months Ended
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Sep. 30, 2019 shares
Common Stock Oustanding [Roll Forward] |
Shares outstanding, January 1, 2019 (in shares) | 236,063,279
Shareowner Direct Plan (in shares) | 390,630
Equity-based compensation plans (in shares) | 101,478
Other (in shares) | (2,738)
Shares outstanding, September 30, 2019 (in shares) | 240,342,949
Equity Forward Agreements [Member] |
Common Stock Oustanding [Roll Forward] |
Equity forward agreements (in shares) | 3,790,300

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