WILDFIRE-RELATED CONTINGENCIES (Summary of Insurance Receivables) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Insurance Receivable [Roll Forward]
Wildfire-related insurance receivable	$ 25	$ 197
2018 Camp fire
Insurance Receivable [Roll Forward]
Insurance Receivable, Beginning Balance	1,380
Accrued insurance recoveries	0
Wildfire-related insurance receivable	0
Insurance Receivable, Ending Balance	1,380
2017 Northern California wildfires
Insurance Receivable [Roll Forward]
Insurance Receivable, Beginning Balance	829
Accrued insurance recoveries	0
Wildfire-related insurance receivable	0
Insurance Receivable, Ending Balance	$ 829