Condensed Statements Of Consolidated Comprehensive Income (Parenthetical) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Statement of Comprehensive Income [Abstract]
Reclassification to interest income of mark-to-market valuations of holdings of affiliate debt (net of tax expense of $—, $—, $— and $99) (Note 10)	$ 0	$ 0	$ 0	$ 99
Net effects related to Oncor — reported in equity in earnings of unconsolidated subsidiaries (net of tax benefit of $— in all periods)	$ 0	$ 0	$ 0	$ 0