CONTINGENCIES AND COMMITMENTS (Northern California Wildfires) (Details) insurance_claim in Thousands, a in Thousands, $ in Thousands			3 Months Ended
	May 01, 2018 lawsuit complaint plaintiff	Jan. 31, 2018 USD ($) vehicle insurance_claim home business	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)	Apr. 30, 2018 USD ($) incident_report	Feb. 03, 2018 wildfire outbuilding home	Nov. 20, 2017 lawsuit	Oct. 30, 2017 a wildfire fatality structure
Loss Contingencies [Line Items]
Capital expenditures			$ 255,000	$ 237,000
Loss from Catastrophes | Lawsuits Against PG&E Corporation and the Utility in the Sonoma, Napa and San Francisco Counties Superior Courts | Subsequent Event
Loss Contingencies [Line Items]
Number of lawsuits filed against company (lawsuit) | lawsuit	150
Number of plaintiffs in lawsuit (plaintiff) | plaintiff	2,500
Loss from Catastrophes | Lawsuits Against PG&E Corporation and the Utility in the Sonoma, Napa and San Francisco Counties Superior Courts, Classified As Class Actions | Subsequent Event
Loss Contingencies [Line Items]
Number of lawsuits filed against company (lawsuit) | lawsuit	6
Loss from Catastrophes | Subrogation Complaints Against PG&E Corporation and the Utility in San Francisco County Superior Courts | Subsequent Event
Loss Contingencies [Line Items]
Number of lawsuits filed against company (lawsuit) | complaint	8
Breach of Fiduciary Duties | Derivative Lawsuits Filed in the San Francisco County Superior Court
Loss Contingencies [Line Items]
Number of lawsuits filed against company (lawsuit) | lawsuit							2
Nothern California Wild Fire
Loss Contingencies [Line Items]
Number wildfires (wildfire) | wildfire								21
Number of acres burned (acre) | a								245
Number structures destroyed (structure) | structure								8,900
Number of fatalities caused by fire (fatality) | fatality								44
Service restoration and repair costs			259,000
Capital expenditures			108,000
Insurance claims received by insurers (insurance claim) | insurance_claim		45
Total insurance claims received by insurers		$ 11,790,000
Statewide insurance claims related to wildfire		$ 10,000,000
Number homes damaged by wildfire (home) | home		21,000
Number of businesses damaged by wildfire (business) | business		3,200
Number of vehicles damaged by wildfire (vehicle) | vehicle		6,100
Liability insurance coverage			840,000
Initial self-insured retention per occurrence			10,000
Further retention per occurrence			40,000
Reinstated liability insurance			$ 630,000
Nothern California Wild Fire | Subsequent Event
Loss Contingencies [Line Items]
Number of electric incident reports submitted (incident report) | incident_report					23
Property damage coverage per incident					$ 50
Nothern California Wild Fire | Santa Rosa Investigations
Loss Contingencies [Line Items]
Number wildfires (wildfire) | wildfire						2
Number of homes destroyed by fire (home) | home						2
Number of outbuildings damaged by fire (outbuilding) | outbuilding						1