OTHER FINANCIAL DATA - INCOME TAXES (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Tax Expense And Effective Income Tax Rates Disclosure [Line Items]
Income tax expense	$ 295	$ 108	[1]
Effective income tax rate	39.00%	24.00%
San Diego Gas and Electric Company [Member]
Income Tax Expense And Effective Income Tax Rates Disclosure [Line Items]
Income tax expense	$ 90	$ 65	[1]
Effective income tax rate	36.00%	32.00%
Southern California Gas Company [Member]
Income Tax Expense And Effective Income Tax Rates Disclosure [Line Items]
Income tax expense	$ 98	$ 83	[1]
Effective income tax rate	33.00%	29.00%

[1] As adjusted for the adoption of ASU 2016-09 as of January 1, 2016.