REGULATORY ASSETS, LIABILITIES, AND BALANCING ACCOUNTS (Long-Term Regulatory Liabilities) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Dec. 31, 2022	Jun. 30, 2022
Regulatory Liabilities [Line Items]
Total long-term regulatory liabilities	$ 18,884	$ 17,630
Proceeds received from sale of transmission tower wireless licenses, to be refunded to customers	416
Authorized amount of shareholder tax benefits to be returned	7,590
Federal Energy Regulatory Commission
Regulatory Liabilities [Line Items]
Proceeds received from sale of transmission tower wireless licenses, to be refunded to customers	291
California Public Utilities Commission
Regulatory Liabilities [Line Items]
Proceeds received from sale of transmission tower wireless licenses, to be refunded to customers	125
Cost of removal obligations
Regulatory Liabilities [Line Items]
Total long-term regulatory liabilities	8,103	7,773
Public purpose programs
Regulatory Liabilities [Line Items]
Total long-term regulatory liabilities	1,281	1,062
Employee benefit plans
Regulatory Liabilities [Line Items]
Total long-term regulatory liabilities	925	904
Transmission tower wireless licenses
Regulatory Liabilities [Line Items]
Total long-term regulatory liabilities	416	430
SFGO sale
Regulatory Liabilities [Line Items]
Total long-term regulatory liabilities	205	264
SB 901 Securitization
Regulatory Liabilities [Line Items]
Total long-term regulatory liabilities	6,333	5,800	$ 5,540
Wildfire self-insurance
Regulatory Liabilities [Line Items]
Total long-term regulatory liabilities	300	0
Other
Regulatory Liabilities [Line Items]
Total long-term regulatory liabilities	$ 1,321	$ 1,397