DERIVATIVES (Outstanding Derivative Balances) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Derivatives And Hedging Activities [Line Items]
Netting	$ 143	$ 115
Netting	27	25
Commodity Contract | Pacific Gas & Electric Co (Utility)
Derivatives And Hedging Activities [Line Items]
Netting	(42)	(73)
Netting	0	0
Cash Collateral	170	140
Total Derivative Balance	128	67
Commodity Contract | Pacific Gas & Electric Co (Utility) | Current assets – other
Derivatives And Hedging Activities [Line Items]
Netting	58	33
Netting	(9)	0
Cash Collateral	152	115
Total Derivative Balance	201	148
Commodity Contract | Pacific Gas & Electric Co (Utility) | Other noncurrent assets – other
Derivatives And Hedging Activities [Line Items]
Netting	169	136
Netting	0	0
Cash Collateral	0	0
Total Derivative Balance	169	136
Commodity Contract | Pacific Gas & Electric Co (Utility) | Current liabilities – other
Derivatives And Hedging Activities [Line Items]
Gross Derivative Balance	(53)	(38)
Netting	9	0
Cash Collateral	18	15
Total Derivative Balance	(26)	(23)
Commodity Contract | Pacific Gas & Electric Co (Utility) | Noncurrent liabilities – other
Derivatives And Hedging Activities [Line Items]
Gross Derivative Balance	(216)	(204)
Netting	0	0
Cash Collateral	0	10
Total Derivative Balance	$ (216)	$ (194)