Earnings Per Share (Reconciliation Of PG&E Corporation's Income Available For Common Shareholders And Weighted Average Common Shares Outstanding For Calculating Diluted EPS) (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income available for common shareholders	$ 107	$ 31
Weighted average common shares outstanding, basic	493	477
Employee share-based compensation	2	4
Weighted average common shares outstanding, diluted	495	481
Total earnings per common share, diluted	$ 0.22	$ 0.06