CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Millions		3 Months Ended
		Mar. 31, 2016	Mar. 31, 2015
REVENUES
Utilities		$ 2,442	$ 2,422
Energy-related businesses		180	260
Total revenues		2,622	2,682
Utilities [Abstract]
Cost of natural gas		(311)	(346)
Cost of electric fuel and purchased power		(515)	(481)
Energy-related businesses [Abstract]
Cost of natural gas, electric fuel and purchased power		(56)	(98)
Other cost of sales		(35)	(35)
Operation and maintenance		(701)	(658)
Depreciation and amortization		(328)	(303)
Plant closure adjustment (loss)		0	21
Franchise fees and other taxes		(111)	(107)
Equity Earnings Losses Before Income Tax [Abstract]
Equity (losses) earnings, before income tax		(22)	19
Other income (expense), net		49	39
Interest income		6	7
Interest expense		(143)	(134)
Income (loss) before income taxes and equity earnings of certain unconsolidated subsidiaries		455	606
Income tax (expense) benefit		(142)	(163)
Equity earnings, net of income tax		17	15
Net income (loss)		330	458
Losses (earnings) attributable to noncontrolling interests		(11)	(21)
Earnings (losses)		$ 319	$ 437
Basic earnings per common share:
Basic earnings per common share		$ 1.28	$ 1.76
Basic earnings per common share, weighted-average number of shares outstanding (thousands)	[1]	249,734	247,722
Diluted earnings per common share:
Diluted earnings per common share		$ 1.27	$ 1.74
Diluted earnings per common share, weighted-average number of shares outstanding (thousands)		251,412	251,206
Dividends declared per share of common stock		$ 0.76	$ 0.7
San Diego Gas and Electric Company [Member]
Utility operating revenues
Electric		$ 843	$ 805
Natural gas		148	161
Total utility operating revenues		991	966
Utility operating expenses
Utility cost of electric fuel and purchased power		248	228
Utility cost of natural gas		39	54
Utility operation and maintenance		246	217
Utility depreciation and amortization		159	145
Utility franchise fees and other taxes		63	61
Utility plant closure (adjustment) loss		0	(21)
Total utility operating expenses		755	684
Utility operating income (loss)		236	282
Equity Earnings Losses Before Income Tax [Abstract]
Other income (expense), net		14	9
Interest expense		(48)	(52)
Income (loss) before income taxes and equity earnings of certain unconsolidated subsidiaries		202	239
Income tax (expense) benefit		(72)	(88)
Net income (loss)		130	151
Losses (earnings) attributable to noncontrolling interests		(1)	(4)
Earnings (losses)		129	147
Southern California Gas Company [Member]
Utility operating revenues
Total utility operating revenues		1,033	1,048
Utility operating expenses
Utility cost of natural gas		253	267
Utility operation and maintenance		327	314
Utility depreciation and amortization		122	113
Utility franchise fees and other taxes		37	34
Total utility operating expenses		739	728
Utility operating income (loss)		294	320
Equity Earnings Losses Before Income Tax [Abstract]
Other income (expense), net		10	8
Interest expense		(22)	(19)
Income (loss) before income taxes and equity earnings of certain unconsolidated subsidiaries		282	309
Income tax (expense) benefit		(87)	(95)
Net income (loss)		195	214
Earnings (losses)		$ 195	$ 214

[1] Includes 555 and 452 average fully vested restricted stock units held in our Deferred Compensation Plan for the three months ended March 31, 2016 and 2015, respectively. These fully vested restricted stock units are included in weighted-average common shares outstanding for basic EPS because there are no conditions under which the corresponding shares will not be issued.