Condensed Consolidated Statements Of Comprehensive Income (Parenthetical) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Unrecognized prior service credit income tax	$ 5	$ 7	$ 15	$ 18
Unrecognized net gain income tax	12	6	38	17
Unrecognized net transition obligation income tax	2	3	6	7
Transfer to regulatory account of income	14	8	44	26
Pacific Gas And Electric Company [Member]
Unrecognized prior service credit income tax	5	7	15	18
Unrecognized net gain income tax	12	6	38	17
Unrecognized net transition obligation income tax	2	3	6	7
Transfer to regulatory account of income	$ 14	$ 8	$ 44	$ 26