CONTINGENCIES AND COMMITMENTS (Schedule of Environmental Remediation Liability) (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Topock natural gas compressor station	$ 362	$ 334
Hinkley natural gas compressor station	151	147
Former manufactured gas plant sites owned by the Utility or third parties	375	320
Utility-owned generation facilities (other than fossil fuel-fired), other facilities, and third-party disposal sites	116	115
Fossil fuel-fired generation facilities and sites	136	123
Total environmental remediation liability	$ 1,140	$ 1,039