Consolidated Statement of Changes in Shareholders Equity (Unaudited) (Parenthetical) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Other comprehensive income, income taxes	$ (79)	$ 1	$ (82)	$ (67)
Accumulated Other Comprehensive (Loss) Income, Net
Other comprehensive income, income taxes			159
Exelon Generation Co L L C [Member]
Other comprehensive income, income taxes	102	84	112	152
Exelon Generation Co L L C [Member] | Accumulated Other Comprehensive (Loss) Income, Net
Other comprehensive income, income taxes			$ 35