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	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Earnings Per Share [Abstract]
Loss attributable to common shareholders	$ 475	$ 120
Weighted average common shares outstanding, basic (in shares)	1,986	1,985
Add incremental shares from assumed conversions:
Equity Units (in shares)	8	5
Employee share-based compensation (in shares)	140	141
Weighted average common share outstanding, diluted (in shares)	2,134	2,131
Total Loss per common share, diluted (in dollars per share)	$ 0.22	$ 0.06