OTHER CONTINGENCIES AND COMMITMENTS (Wildfire Insurance) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Loss Contingencies [Line Items]
Costs for insurance coverage	$ 360
Pacific Gas & Electric Co
Loss Contingencies [Line Items]
Costs for insurance coverage	50
Insurance Coverage for Wildfire Events
Loss Contingencies [Line Items]
Liability insurance coverage		$ 1,400
Insurance Coverage for Wildfire Liabilities
Loss Contingencies [Line Items]
Liability insurance coverage		700
Catastrophic bond reinsurance instrument		10
Insurance Coverage for Property Damages
Loss Contingencies [Line Items]
Liability insurance coverage		700
Catastrophic bond reinsurance instrument		$ 200
2018 Camp fire
Loss Contingencies [Line Items]
Estimated insurance recoveries	1,380
2017 Northern California wildfires
Loss Contingencies [Line Items]
Estimated insurance recoveries	$ 842