WILDFIRE-RELATED CONTINGENCIES (Clean-up and Repair Costs) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Loss Contingencies [Line Items]
Capital expenditures	$ 981	$ 348
Total long-term regulatory assets	5,711		$ 4,964
Catastrophic event memorandum account
Loss Contingencies [Line Items]
Total long-term regulatory assets	954		790
Pacific Gas & Electric Co
Loss Contingencies [Line Items]
Capital expenditures	981	$ 348
Total long-term regulatory assets	5,711		$ 4,964
Pacific Gas & Electric Co | 2018 Camp Fire
Loss Contingencies [Line Items]
Service restoration and repair costs	704
Capital expenditures	270
Pacific Gas & Electric Co | 2017 Northern California wildfires
Loss Contingencies [Line Items]
Service restoration and repair costs	346
Capital expenditures	171
Pacific Gas & Electric Co | Catastrophic event memorandum account | 2018 Camp Fire
Loss Contingencies [Line Items]
Total long-term regulatory assets	0
Pacific Gas & Electric Co | Catastrophic event memorandum account | 2017 Northern California wildfires
Loss Contingencies [Line Items]
Total long-term regulatory assets	$ 88