Earnings Per Share and Equity (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Earnings Per Share And Equity Additional Narrative Information [Abstract]
Stock options not included in the calculation of diluted common shares outstanding	16	17	16	18
Treasury Stock, Shares held	35		35		35
Treasury stock, at cost	$ 2,327		$ 2,327		$ 2,327
Earnings Per Share Diluted
Net income on common stock	522	490	612	486
Average common shares outstanding - basic	860	856	860	856
Assumed exercise of stock options, performance share awards and restricted stock	4	4	3	3
Average common shares outstanding - diluted	864	860	863	859
Preferred Stock [Member] | Cumulative Preferred Stock [Member]
Preferred Stock [Line Items]
PECO Cumulative Preferred Securities Redeemable
Retained Earnings | Cumulative Preferred Stock [Member]
Preferred Stock [Line Items]
Preferred stock redemption premium