SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Wildfire Fund (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Public Utility, Property, Plant and Equipment [Line Items]
Litigation liability, current	$ 193
Wildfire Fund asset	450	$ 460
Litigation contribution, net	4,300
Amortization and accretion	567	477	$ 517
Insurance receivable	436	794
2021 Dixie fire
Public Utility, Property, Plant and Equipment [Line Items]
Insurance receivable	326	530
Pacific Gas & Electric Co (Utility)
Public Utility, Property, Plant and Equipment [Line Items]
Wildfire Fund asset	450	460
Amortization and accretion	567	$ 477	$ 517
Other Current Liabilities
Public Utility, Property, Plant and Equipment [Line Items]
Wildfire fund, noncurrent	750
Other noncurrent assets – other | 2021 Dixie fire
Public Utility, Property, Plant and Equipment [Line Items]
Insurance receivable	325
Other noncurrent assets – other | Pacific Gas & Electric Co (Utility) | 2021 Dixie fire
Public Utility, Property, Plant and Equipment [Line Items]
Insurance receivable	$ 275