Equity (Changes In Equity) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Balance at December 31, 2011	$ 12,353
Comprehensive income	246	211
Common stock issued	393
Share-based compensation expense	16
Common stock dividends declared	(193)
Preferred stock dividend requirement of subsidiary	(3)	(3)
Balance at March 31, 2012	12,812
Pacific Gas And Electric Company [Member]
Balance at December 31, 2011	12,384
Comprehensive income	241	210
Common stock dividends declared	(179)
Preferred stock dividend requirement	(3)	(3)
Equity contribution	385	65
Balance at March 31, 2012	$ 12,828