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Common Equity (Common Share Activity) (Details) | 9 Months Ended
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Sep. 30, 2015 shares
Common Stock Oustanding [Roll Forward] |
Shares outstanding, January 1, 2015 (in shares) | 110,935,680
New shares of stock issued, Shareowner Direct Plan (in shares) | 204,213
Equity-based compensation plans (in shares) | 56,378
Other (in shares) | (22,463)
Shares outstanding, September 30, 2015 (in shares) | 113,360,425
At The Market Offering Program [Member] |
Common Stock Oustanding [Roll Forward] |
New shares of common stock issued, At-the-market offering program (in shares) | 2,186,617

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