COMMON STOCK AND SHARE-BASED COMPENSATION (Narrative) (Details) - USD ($)	12 Months Ended			60 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2019
Common stock, shares outstanding (in shares)	529,236,741	520,338,710		529,236,741
Cash proceeds from stock issuance	$ 13,038,000,000	$ 12,910,000,000		$ 13,038,000,000
Consolidated total debt to consolidated capitalization, percentage	65.00%			65.00%
Consolidated total debt to consolidated capitalization, equity, percentage	52.00%			52.00%
Period in which cash dividends is not expected to be paid for	2 years
Number of shares issued for LTIP, maximum (in shares)	17,000,000			17,000,000
Shares available for LTIP award (in shares)	12,338,419			12,338,419
Weighted average grant date fair value of granted shares (in dollars per share)	$ 18.57	$ 40.92	$ 66.95
Total fair value	$ 42,000,000	$ 41,000,000	$ 57,000,000
Total unrecognized compensation costs	$ 19,000,000
Remaining weighted average period	1 year 1 month 20 days
Pacific Gas & Electric Co
Common stock, shares outstanding (in shares)	264,374,809	264,374,809		264,374,809
Cash proceeds from stock issuance	$ 1,322,000,000	$ 1,322,000,000		$ 1,322,000,000
Stock Options
Tax benefit from share based awards	$ 0
Weighted-average period	1 year 2 months 1 day
Stock Options | 2014 LTIP
Term of award	10 years
Award vesting period	3 years
Total unrecognized compensation costs	$ 10,500,000			$ 10,500,000
Weighted average grant date fair value of granted shares (in dollars per share)	$ 3.87	$ 10.24
Restricted stock units
Award vesting period				3 years
Performance shares
Award vesting period	3 years
Tax benefit from share based awards	$ 0	$ 0	$ 0
Industry performance period	3 years
Award grant date fair value recognition period	3 years
Performance shares granted (in dollars per share)	$ 15.39	$ 36.92	$ 77.00
Employee service share based compensation nonvested performance shares total compensation cost not yet recognized	$ 11,000,000
Expirations, fair value (in dollars per share)	$ 0
February 2017 Equity Distribution Agreement
Common stock issued (in shares)	0			0
Common stock, gross sales available	$ 246,000,000			$ 246,000,000
Dividend Reinvestment and Stock Purchase Plan
Common stock issued (in shares)	8,900,000			8,900,000
Cash proceeds from stock issuance	$ 85,000,000			$ 85,000,000
PG&E Corporation
Cash proceeds from stock issuance	$ 13,038,000,000	$ 12,910,000,000		$ 13,038,000,000
unrecognized compensation cost, period	1 year 8 months 23 days