WILDFIRE-RELATED CONTINGENCIES (Potential Losses in Connection with the 2018 Camp Fire and 2017 Northern California Wildfires) (Details) insurance_claim in Thousands, $ in Millions			12 Months Ended
	Jan. 28, 2019 USD ($)	Sep. 06, 2018 USD ($) insurance_claim	Dec. 31, 2018 USD ($)	Dec. 31, 2015 USD ($)	Mar. 31, 2019 USD ($)
November 2018 Fires
Loss Contingencies [Line Items]
Total insurance claims received by insurers (more than)	$ 11,400
2018 Camp fire
Loss Contingencies [Line Items]
Total insurance claims received by insurers (more than)	8,400
Loss in period			$ 10,500
2017 Northern California wildfires
Loss Contingencies [Line Items]
Total insurance claims received by insurers (more than)		$ 12,280
Insurance claims received by insurers (insurance claim) | insurance_claim		55
Statewide insurance claims related to wildfire		$ 10,000
2018 Camp Fire and 2017 Northern California Wildfires
Loss Contingencies [Line Items]
Total insurance claims received by insurers (more than)	$ 18,400
Estimate of possible losses					$ 30,000
Pacific Gas & Electric Co | San Bruno Natural Gas Explosion
Loss Contingencies [Line Items]
Loss in period				$ 1,600
Loss contingency liability				$ 558