OTHER CONTINGENCIES AND COMMITMENTS (Wildfire Insurance) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Maximum
Loss Contingencies [Line Items]
Costs for insurance coverage	$ 1,400
August 1, 2019 through September 2, 2020
Loss Contingencies [Line Items]
Costs for insurance coverage	212
Pacific Gas & Electric Co
Loss Contingencies [Line Items]
Costs for insurance coverage	50
Insurance Coverage for Property Damages
Loss Contingencies [Line Items]
Liability insurance coverage		$ 700
Insurance Coverage for Wildfire Events
Loss Contingencies [Line Items]
Liability insurance coverage	430
Insurance Coverage for Wildfire Events | August 1, 2019 through July 31, 2020
Loss Contingencies [Line Items]
Liability insurance coverage	430
Catastrophic bond reinsurance instrument	10
Insurance Coverage For Non-Wildfire Liabilities | August 1, 2019 through July 31, 2020
Loss Contingencies [Line Items]
Liability insurance coverage	1,000
Insurance Coverage for Wildfire Liabilities
Loss Contingencies [Line Items]
Liability insurance coverage	1,000
Catastrophic bond reinsurance instrument	10
Insurance Coverage for Wildfire Liabilities | August 1, 2019 through July 31, 2020
Loss Contingencies [Line Items]
Liability insurance coverage	520
Insurance Coverage for Wildfire Liabilities | August 1, 2019 through July 31, 2020
Loss Contingencies [Line Items]
Liability insurance coverage	520
Catastrophic bond reinsurance instrument	10
Insurance Coverage for Wildfire Liabilities | September 3, 2019 through September 2, 2020
Loss Contingencies [Line Items]
Liability insurance coverage	480
2018 Camp fire
Loss Contingencies [Line Items]
Settlement reached	1,380
2017 Northern California wildfires
Loss Contingencies [Line Items]
Settlement reached	$ 843