Condensed Consolidated Statements Of Comprehensive Income (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
Unrealized Gains (Losses) on Available-for-Sale Securities, tax	$ (9)	$ 16	$ (12)	$ (11)
Unrealized Gains (Losses) on Cash Flow Hedges, tax	0	1	(2)	3
Pension/OPEB adjustment, tax	(1)	(7)	(3)	(14)
Power [Member]
Unrealized Gains (Losses) on Available-for-Sale Securities, tax	(9)	16	(11)	(11)
Unrealized Gains (Losses) on Cash Flow Hedges, tax	(1)	1	(2)	3
Pension/OPEB adjustment, tax	$ (1)	$ (6)	$ (3)	$ (11)