EARNINGS PER SHARE (Reconciliation of PG&E Corporation's Income Available for Common Shareholders and Weighted Average Shares of Common Stock Outstanding for Calculating Diluted EPS) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share [Abstract]
Income (loss) available for common shareholders	$ (7,656)	$ (6,851)	$ 1,646
Weighted average common shares outstanding, basic	528	517	512
Add incremental shares from assumed conversions:
Employee share-based compensation (in shares)	0	0	1
Weighted average common share outstanding, diluted (in shares)	528	517	513
Total earnings (loss) per common share, diluted (in dollars per share)	$ (14.50)	$ (13.25)	$ 3.21