INCOME TAXES (Schedule of Change in Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pacific Gas & Electric Co (Utility)
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance, beginning of period	$ 437	$ 420	$ 377
Reductions for tax position taken during a prior year	(23)	(43)	(1)
Additions for tax position taken during the current year	85	60	44
Settlements	(1)	0	0
Balance, end of period	498	437	420
PG&E Corporation
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance, beginning of period	437	420	377
Reductions for tax position taken during a prior year	(23)	(43)	(1)
Additions for tax position taken during the current year	85	60	44
Settlements	(1)	0	0
Balance, end of period	$ 498	$ 437	$ 420