SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Revenues Disaggregated by Type of Customer) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Disaggregation of Revenue [Abstract]
Total operating revenues	$ 6,209	$ 5,798
Electric
Disaggregation of Revenue [Abstract]
Total operating revenues	4,119	4,158
Natural gas
Disaggregation of Revenue [Abstract]
Total operating revenues	2,090	1,640
Pacific Gas & Electric Co (Utility)
Disaggregation of Revenue [Abstract]
Total operating revenues	6,209	5,798
Pacific Gas & Electric Co (Utility) | Electric
Disaggregation of Revenue [Abstract]
Total operating revenues	3,003	3,237
Regulatory balancing accounts	1,116	921
Total operating revenues	4,119	4,158
Pacific Gas & Electric Co (Utility) | Electric | Residential
Disaggregation of Revenue [Abstract]
Total operating revenues	1,289	1,494
Pacific Gas & Electric Co (Utility) | Electric | Commercial
Disaggregation of Revenue [Abstract]
Total operating revenues	1,144	1,173
Pacific Gas & Electric Co (Utility) | Electric | Industrial
Disaggregation of Revenue [Abstract]
Total operating revenues	353	350
Pacific Gas & Electric Co (Utility) | Electric | Agricultural
Disaggregation of Revenue [Abstract]
Total operating revenues	155	216
Pacific Gas & Electric Co (Utility) | Electric | Public street and highway lighting
Disaggregation of Revenue [Abstract]
Total operating revenues	19	18
Pacific Gas & Electric Co (Utility) | Electric | Other, net
Disaggregation of Revenue [Abstract]
Total operating revenues	43	(14)
Pacific Gas & Electric Co (Utility) | Natural gas
Disaggregation of Revenue [Abstract]
Total operating revenues	2,687	2,027
Regulatory balancing accounts	(597)	(387)
Total operating revenues	2,090	1,640
Pacific Gas & Electric Co (Utility) | Natural gas | Residential
Disaggregation of Revenue [Abstract]
Total operating revenues	1,883	1,464
Pacific Gas & Electric Co (Utility) | Natural gas | Commercial
Disaggregation of Revenue [Abstract]
Total operating revenues	513	344
Pacific Gas & Electric Co (Utility) | Natural gas | Transportation service only
Disaggregation of Revenue [Abstract]
Total operating revenues	444	399
Pacific Gas & Electric Co (Utility) | Natural gas | Other, net
Disaggregation of Revenue [Abstract]
Total operating revenues	$ (153)	$ (180)