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		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Income available for common shareholders	$ 550	$ 388	$ 1,532	$ 701
Weighted average common shares outstanding, basic	513	501	511	497
Employee share-based compensation	3	2	3	3
Weighted average common shares outstanding, diluted	516	503	514	500
Total earnings per common share, diluted	$ 1.07	$ 0.77	$ 2.98	$ 1.40