CONTINGENCIES AND COMMITMENTS (Schedule of Environmental Remediation Liability) (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Topock natural gas compressor station	$ 342	$ 334
Hinkley natural gas compressor station	144	147
Former manufactured gas plant sites owned by the Utility or third parties	329	320
Utility-owned generation facilities (other than fossil fuel-fired), other facilities, and third-party disposal sites	113	115
Fossil fuel-fired generation facilities and sites	157	123
Total environmental remediation liability	$ 1,085	$ 1,039