SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Wildfire Fund) (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($) contribution	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) contribution	Sep. 30, 2019 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)
Loss Contingencies [Line Items]
Initial contribution payment	$ 4,800		$ 4,800
Annual contribution, first payment	$ 193		$ 193
Number of remaining annual contributions | contribution	9		9
Litgation liability, current					$ 5,200
Litigation contribution, net					6,500
Wildfire fund asset	$ 5,932		$ 5,932		6,000	$ 0
Wildfire fund expense	$ 120	$ 0	$ 293	$ 0
Monte carlo simulation, historical data, period			12 years
Historical data period			12 years
Amortization period			6 years
Percentage assumption change	10.00%		10.00%
Greater effectiveness, amortization period			17 years
Less effectiveness, amortization period			12 years
Pacific Gas & Electric Co
Loss Contingencies [Line Items]
Wildfire fund asset	$ 5,932		$ 5,932			$ 0
Wildfire fund expense	120	$ 0	293	$ 0
5 year period
Loss Contingencies [Line Items]
Average annual statewide claims or settlements	6,500		$ 6,500
Historical data period			5 years
12 year period
Loss Contingencies [Line Items]
Average annual statewide claims or settlements	$ 2,900		$ 2,900
Wildfire Fund asset
Loss Contingencies [Line Items]
Finite-lived intangible asset, useful life			15 years
Noncurrent liabilities – other
Loss Contingencies [Line Items]
Wildfire fund, noncurrent					$ 1,500