WILDFIRE-RELATED CONTINGENCIES (Insurance) (Details) - USD ($) $ in Millions		1 Months Ended	6 Months Ended
	Apr. 29, 2021	Jun. 30, 2021	Jun. 30, 2021	Aug. 31, 2020
Loss Contingencies [Line Items]
Prepaid Insurance		$ 301	$ 301
Insurance premium costs, recovery, coverage amount		1,400	1,400
Insurance Coverage for Wildfire Events
Loss Contingencies [Line Items]
Initial self-insured retention per occurrence		60	60
Insurance Coverage for Wildfire Events | April 13, 2021 to April 1, 2022
Loss Contingencies [Line Items]
Liability insurance coverage	$ 268
Reinsurance	32
Costs for insurance coverage	$ 220
Insurance Coverage for Wildfire Events | July 1, 2020 to July 1, 2021
Loss Contingencies [Line Items]
Reinsurance				$ 11
Insurance Coverage for Wildfire Events | August 1, 2020 to August 1, 2021
Loss Contingencies [Line Items]
Liability insurance coverage				$ 600
Insurance Coverage for Wildfire Events | August 1, 2021 to August 1, 2022
Loss Contingencies [Line Items]
Costs for insurance coverage			516
Insurance Coverage for Wildfire Events | June 1, 2021 to April 1, 2022
Loss Contingencies [Line Items]
Costs for insurance coverage		89
Insurance Coverage For Non-Wildfire Events
Loss Contingencies [Line Items]
Initial self-insured retention per occurrence		10	10
Insurance Coverage For Non-Wildfire Events | April 13, 2021 to April 1, 2022
Loss Contingencies [Line Items]
Liability insurance coverage		50	50
Insurance Coverage For Non-Wildfire Events | August 1, 2020 to August 1, 2021
Loss Contingencies [Line Items]
Liability insurance coverage		140	140
Insurance Coverage For Non-Wildfire Events | June 1, 2021 to April 1, 2022
Loss Contingencies [Line Items]
Liability insurance coverage		535	$ 535
Insurance Coverage For Non-Wildfire Events | Extension to April 1, 2022
Loss Contingencies [Line Items]
Costs for insurance coverage		$ 30