CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash Flows from Financing Activities
Discount on net issuances of commercial paper	$ 0	$ 0	$ 1
Issuance costs for short-term debt	2	0	0
Premium, discount, and issuance costs on proceeds from long-term debt	178	0	7
Pacific Gas & Electric Co (Utility)
Cash Flows from Financing Activities
Discount on net issuances of commercial paper	0	0	0
Issuance costs for short-term debt	2	0	0
Premium, discount, and issuance costs on proceeds from long-term debt	$ 88	$ 0	$ 7