OTHER CONTINGENCIES AND COMMITMENTS (Station Sites, Gas Plants, Generation Facilities and Disposal Sites) (Details) $ in Millions	Mar. 31, 2021 USD ($)
Topock Site
Long-term Purchase Commitment [Line Items]
Amount of environmental loss actual expected to be recovered	$ 220
Topock Site | Pacific Gas & Electric Co (Utility)
Long-term Purchase Commitment [Line Items]
Remediation cost recovery percentage	90.00%
Hinkley Natural Gas Compressor Station
Long-term Purchase Commitment [Line Items]
Amount of environmental loss actual expected to be recovered	$ 138
Former Manufactured Gas Plant
Long-term Purchase Commitment [Line Items]
Amount of environmental loss actual expected to be recovered	$ 436
Remediation cost recovery percentage	90.00%
Utility Owned Generation Facilities and Third Party Disposal Sites
Long-term Purchase Commitment [Line Items]
Amount of environmental loss actual expected to be recovered	$ 59
Utility Owned Generation Facilities and Third Party Disposal Sites | Pacific Gas & Electric Co (Utility)
Long-term Purchase Commitment [Line Items]
Remediation cost recovery percentage	90.00%
Fossil Fuel Fired Generation
Long-term Purchase Commitment [Line Items]
Amount of environmental loss actual expected to be recovered	$ 44