GENERAL INFORMATION AND OTHER FINANCIAL DATA - CASH, CASH EQUIVALENTS AND RESTRICTED CASH (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 106	$ 102	[1]
Restricted cash, current	28	35	[1]
Restricted cash, noncurrent	3	21	[1]
Cash and cash equivalents	360	88
Total cash, cash equivalents and restricted cash on the Condensed Consolidated Statements of Cash Flows	497	246
San Diego Gas and Electric Company [Member]
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	24	8	[1]
Restricted cash, current	0	11	[1]
Restricted cash, noncurrent	0	18	[1]
Total cash, cash equivalents and restricted cash on the Condensed Consolidated Statements of Cash Flows	$ 24	$ 37

[1] Derived from audited financial statements.