CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Property, plant and equipment, net related to VIE	$ 321	$ 354
Long term debt related to VIE	$ 284	$ 293
Stockholders' Equity Attributable to Parent [Abstract]
Preferred stock, shares authorized	50,000,000	50,000,000
Preferred stock, shares issued	0	0
Common stock, shares authorized	750,000,000	750,000,000
Common stock, shares outstanding	251,358,977	250,152,514
Common stock par value (in dollars per share)	$ 0	$ 0
San Diego Gas and Electric Company [Member]
Property, plant and equipment, net related to VIE	$ 321	$ 354
Long term debt related to VIE	$ 284	$ 293
Stockholders' Equity Attributable to Parent [Abstract]
Preferred stock, shares authorized	45,000,000	45,000,000
Preferred stock, shares outstanding	0
Preferred stock, shares issued	0	0
Common stock, shares authorized	255,000,000	255,000,000
Common stock, shares outstanding	117,000,000	117,000,000
Common stock par value (in dollars per share)	$ 0	$ 0
Southern California Gas Company [Member]
Stockholders' Equity Attributable to Parent [Abstract]
Preferred stock, shares authorized	11,000,000	11,000,000
Preferred stock, shares outstanding	1,000,000	1,000,000
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares outstanding	91,000,000	91,000,000