REVENUES - RECEIVABLES FROM REVENUES FROM CONTRACTS WITH CUSTOMERS (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Contract with Customer, Asset [Line Items]
Receivables from revenues from contracts with customers	$ 1,154	$ 1,184
Accounts receivable – trade, net [Member]
Contract with Customer, Asset [Line Items]
Receivables from revenues from contracts with customers	1,142	1,163
Accounts receivable – other, net [Member]
Contract with Customer, Asset [Line Items]
Receivables from revenues from contracts with customers	8	16
Due from unconsolidated affiliates – current [Member]
Contract with Customer, Asset [Line Items]
Receivables from revenues from contracts with customers	4	5
San Diego Gas and Electric Company [Member]
Contract with Customer, Asset [Line Items]
Receivables from revenues from contracts with customers	421	405
San Diego Gas and Electric Company [Member] | Accounts receivable – trade, net [Member]
Contract with Customer, Asset [Line Items]
Receivables from revenues from contracts with customers	411	398
San Diego Gas and Electric Company [Member] | Accounts receivable – other, net [Member]
Contract with Customer, Asset [Line Items]
Receivables from revenues from contracts with customers	7	5
San Diego Gas and Electric Company [Member] | Due from unconsolidated affiliates – current [Member]
Contract with Customer, Asset [Line Items]
Receivables from revenues from contracts with customers	3	2
Southern California Gas Company [Member]
Contract with Customer, Asset [Line Items]
Receivables from revenues from contracts with customers	670	721
Southern California Gas Company [Member] | Accounts receivable – trade, net [Member]
Contract with Customer, Asset [Line Items]
Receivables from revenues from contracts with customers	669	710
Southern California Gas Company [Member] | Accounts receivable – other, net [Member]
Contract with Customer, Asset [Line Items]
Receivables from revenues from contracts with customers	$ 1	$ 11