Earnings Per Share (Reconciliation of PG&E Corporation's Income Available for Common Shareholders and Weighted Average Shares of Common Stock Outstanding for Calculating Basic EPS) (Details) (USD $) In Millions, except Per Share data	3 Months Ended				6 Months Ended
	Jun. 30, 2011		Jun. 30, 2010		Jun. 30, 2011		Jun. 30, 2010
Earnings Per Share
Income available for common shareholders	$ 362		$ 333		$ 561		$ 591
Less: distributed earnings to common shareholders			178				347
Undistributed Earnings, Basic, Total		[1]	155			[1]	244
Distributed earnings to common shareholders			178				347
Undistributed earnings allocated to common shareholders			149				234
Total common shareholders earnings		[1]	$ 327			[1]	$ 581
Weighted average common shares outstanding, basic	399		373		397		372
Convertible subordinated notes			15				16
Weighted average common shares outstanding and participating securities	399		388		397		388
Earnings Per Share, Basic, Distributed		[1],[2]	$ 0.48	[2]		[1],[2]	$ 0.93	[2]
Earnings Per Share, Basic, Undistributed		[1]	$ 0.40			[1]	$ 0.63
Total	$ 0.91		$ 0.88		$ 1.41		$ 1.56

[1] EPS for 2011 was calculated by dividing the income available for common shareholders by the weighted average number of common shares outstanding.

[2] Distributed earnings, basic may differ from actual per share amounts paid as dividends, as the EPS computation under GAAP requires the use of the weighted average, rather than the actual, number of shares outstanding.