WILDFIRE-RELATED CONTINGENCIES (Loss Recoveries) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Jul. 31, 2019	Jul. 08, 2019	Dec. 31, 2018	Jul. 31, 2018
2018 Camp Fire and 2017 Northern California Wildfires
Loss Contingencies [Line Items]
Liability insurance coverage		$ 1,400			$ 842
Initial self-insured retention per occurrence		10			10
Further retention per occurrence					$ 40
Liability insurance coverage, general liability		700
Liability insurance coverage, property damages		700
Liability insurance coverage, property damages, reinsurance		$ 200
Customer Harm Threshold, potential regulatory adjustment, percentage			20.00%
Customer Harm Threshold, potential regulatory adjustment, percentage of total disallowed wildlife liability			5.00%
2018 Camp Fire
Loss Contingencies [Line Items]
Estimated insurance recoveries	$ 1,380
Insurance settlements receivable	1,380
2017 Northern California wildfires
Loss Contingencies [Line Items]
Estimated insurance recoveries	842
Insurance settlements receivable	$ 807			$ 829