CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
REVENUES
Utilities	$ 8,322	$ 7,019	$ 6,421
Energy Related Businesses	1,714	1,984	1,685
Total revenues	10,036	9,003	8,106
Utilities [Abstract]
Cost of natural gas	(1,866)	(2,012)	(1,645)
Cost of electric fuel and purchased power	(1,397)	(637)	(672)
Energy-related businesses [Abstract]
Cost of natural gas, electric fuel and purchased power	(746)	(1,046)	(864)
Other cost of sales	(137)	(88)	(77)
Litigation expense	(37)	(169)	(4)
Other operation and maintenance	(2,788)	(2,499)	(2,467)
Depreciation and amortization	(978)	(867)	(775)
Franchise fees and other taxes	(343)	(327)	(296)
Write-off of long-lived assets			(132)
Equity Earnings (Losses) [Abstract]
RBS Sempra Commodities LLP	(24)	(314)	463
Other	33	22	36
Remeasurement of equity method investments	277
Other income (expense), net	130	140	149
Interest income	26	16	21
Interest expense	(465)	(436)	(367)
Income before income taxes and equity earnings of certain unconsolidated subsidiaries	1,721	786	1,476
Income tax (expense) benefit	(366)	(102)	(422)
Equity earnings, net of income tax	52	49	68
Net income	1,407	733	1,122
Losses (earnings) attributable to noncontrolling interests	(42)	16	7
Preferred dividends of subsidiaries	(8)	(10)	(10)
Earnings	1,357	739	1,119
Basic earnings per common share:
Basic earnings per common share	$ 5.66	$ 3.02	$ 4.60
Basic earnings per common share, weighted-average number of shares outstanding (thousands)	239,720	244,736	243,339
Diluted earnings per common share:
Diluted earnings per common share	$ 5.62	$ 2.98	$ 4.52
Diluted earnings per common share, weighted-average number of shares outstanding (thousands)	241,523	247,942	247,384
Dividends declared per share of common stock	$ 1.92	$ 1.56	$ 1.56
San Diego Gas and Electric Company and Subsidiary [Member]
Utility operating revenues
Electric	2,830	2,535	2,426
Natural gas	543	514	490
Total utility operating revenues	3,373	3,049	2,916
Utility operating expenses
Utility cost of natural gas	226	217	206
Utility cost of electric fuel and purchased power	715	637	672
Utility operation and maintenance	1,072	987	960
Utility depreciation and amortization	422	381	329
Utility franchise fees and other taxes	183	170	160
Total utility operating expenses	2,618	2,392	2,327
Utility operating income	755	657	589
Equity Earnings (Losses) [Abstract]
Other income (expense), net	79	10	64
Interest income			1
Interest expense	(142)	(136)	(104)
Income before income taxes and equity earnings of certain unconsolidated subsidiaries	692	531	550
Income tax (expense) benefit	(237)	(173)	(177)
Net income	455	358	373
Losses (earnings) attributable to noncontrolling interests	(19)	16	(24)
Earnings	436	374	349
Preferred dividend requirements	(5)	(5)	(5)
Earnings attributable to common shares	431	369	344
Southern California Gas Company [Member]
Utility operating revenues
Total utility operating revenues	3,816	3,822	3,355
Utility operating expenses
Utility cost of natural gas	1,568	1,699	1,343
Utility operation and maintenance	1,305	1,174	1,138
Utility depreciation and amortization	331	309	293
Utility franchise fees and other taxes	126	124	105
Total utility operating expenses	3,330	3,306	2,879
Utility operating income	486	516	476
Equity Earnings (Losses) [Abstract]
Other income (expense), net	13	12	7
Interest income	1	1	3
Interest expense	(69)	(66)	(68)
Income before income taxes and equity earnings of certain unconsolidated subsidiaries	431	463	418
Income tax (expense) benefit	(143)	(176)	(144)
Net income	288	287	274
Earnings	288	287	274
Preferred dividend requirements	(1)	(1)	(1)
Earnings attributable to common shares	$ 287	$ 286	$ 273