Common Equity (Common Share Activity) (Details) - shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Common Stock Oustanding [Roll Forward]
Shares outstanding, January 1 (in shares)	236,063,279	231,348,646	227,673,654
Common stock issued during the period, Shareowner Direct Plan (in shares)	501,808	576,965	640,723
Common stock issued during the period, Equity-based compensation plans (in shares)	101,478	5,078	5,185
Common stock issued during the period, Other (in shares)	(2,738)	(38,423)	(45,847)
Shares outstanding, December 31 (in shares)	245,022,800	236,063,279	231,348,646
Equity Forward Agreements [Member]
Common Stock Oustanding [Roll Forward]
Common stock issued during the period (in shares)	8,358,973	0	0
At-the-market Offering Program [Member]
Common Stock Oustanding [Roll Forward]
Common stock issued during the period (in shares)	0	4,171,013	3,074,931