OTHER CONTINGENCIES AND COMMITMENTS (Ex Parte Communication Rules) (Details) - USD ($) $ in Thousands				12 Months Ended
	Sep. 21, 2018	May 17, 2018	Apr. 26, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 05, 2019
Loss Contingencies [Line Items]
Settlement agreement, proposed payment to California general fund						$ 2,000
Accrued legal liabilities				$ 116,000
Other Current Liabilities
Loss Contingencies [Line Items]
Accrued legal liabilities					$ 98,000
Pacific Gas & Electric Co | Electric
Loss Contingencies [Line Items]
Requested revenue rate	98.85%
Ex Parte Communications
Loss Contingencies [Line Items]
Proposed penalty			$ 97,500
Payment to State General Fund		$ 12,000	12,000
Gas transmission and storage revenue reduction			63,500
2018 GT&S revenue requirement reduction			31,750
2019 GT&S revenue requirement reduction			31,750
Revenue requirement reduction in Next GRC cycle			$ 10,000
Payment to city of San Carlos		6,000
Payment to city of San Bruno		$ 6,000
Settlement agreement, proposed penalty						10,000
Settlement agreement, proposed forgone revenue collection, 2019 GT&S rate case						5,000
Settlement agreement, proposed forgone revenue collection, 2020 GRC cycle						1,000
Settlement agreement, proposed compensation payments						2,000
Settlement agreement, proposed compensation payments, San Bruno						$ 1,000
Ex Parte Communications | Pacific Gas & Electric Co
Loss Contingencies [Line Items]
Loss contingency liability				4,000
Disallowance of Plant Costs
Loss Contingencies [Line Items]
Cancelled Capital Project Costs				$ 63,500	$ 63,500