WILDFIRE-RELATED CONTINGENCIES (District Attorneys Offices Investigations) (Details) $ in Millions			12 Months Ended
	Jul. 21, 2020 USD ($)	Mar. 17, 2020 USD ($) count	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Loss Contingencies [Line Items]
Wildfire fund expense			$ 413.0	$ 0.0	$ 0.0
Pacific Gas & Electric Co (Utility)
Loss Contingencies [Line Items]
Wildfire fund expense			$ 413.0	$ 0.0	$ 0.0
Pacific Gas & Electric Co (Utility) | Complaints Brought By Butte County District Attorney | Loss from Wildfires
Loss Contingencies [Line Items]
Number of guilty involuntary manslaughter pleas | count		84
Wildfire fund expense	$ 3.5	$ 3.5
Reimbursement of investigation fees	$ 0.5	0.5
Committed funds for impacted residence		$ 15.0
Committed funds for impacted residence, minimum term		5 years