CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Net income (loss)	$ 102,000,000	$ 719,000,000	$ 802,000,000	$ 1,110,000,000
Other comprehensive income (loss):
Comprehensive income			888,000,000	1,050,000,000
Pretax amount [Member]
Net income (loss)	(27,000,000)	904,000,000	1,136,000,000	1,276,000,000
Other comprehensive income (loss):
Foreign currency translation adjustments	27,000,000	(28,000,000)	76,000,000	51,000,000
Financial instruments	7,000,000	23,000,000	(29,000,000)	(214,000,000)
Pension and other postretirement benefits	11,000,000	4,000,000	16,000,000	8,000,000
Total other comprehensive income (loss)	45,000,000	(1,000,000)	63,000,000	(155,000,000)
Comprehensive income	18,000,000	903,000,000	1,199,000,000	1,121,000,000
Preferred dividends			(1,000,000)	(1,000,000)
Comprehensive income (loss) after preferred dividends of subsidiary			1,198,000,000	1,120,000,000
Income tax (expense) benefit [Member]
Net income (loss)	84,000,000	(282,000,000)	(378,000,000)	(284,000,000)
Other comprehensive income (loss):
Foreign currency translation adjustments	0	0	0	0
Financial instruments	(1,000,000)	(10,000,000)	13,000,000	100,000,000
Pension and other postretirement benefits	(4,000,000)	(2,000,000)	(6,000,000)	(4,000,000)
Total other comprehensive income (loss)	(5,000,000)	(12,000,000)	7,000,000	96,000,000
Comprehensive income	79,000,000	(294,000,000)	(371,000,000)	(188,000,000)
Preferred dividends			0	0
Comprehensive income (loss) after preferred dividends of subsidiary			(371,000,000)	(188,000,000)
Net-of-tax amount [Member]
Net income (loss)	57,000,000	622,000,000	758,000,000	992,000,000
Other comprehensive income (loss):
Foreign currency translation adjustments	27,000,000	(28,000,000)	76,000,000	51,000,000
Financial instruments	6,000,000	13,000,000	(16,000,000)	(114,000,000)
Pension and other postretirement benefits	7,000,000	2,000,000	10,000,000	4,000,000
Total other comprehensive income (loss)	40,000,000	(13,000,000)	70,000,000	(59,000,000)
Comprehensive income	97,000,000	609,000,000	828,000,000	933,000,000
Preferred dividends			(1,000,000)	(1,000,000)
Comprehensive income (loss) after preferred dividends of subsidiary			827,000,000	932,000,000
Noncontrolling Interests (after-tax) [Member]
Net income (loss)	45,000,000	97,000,000	44,000,000	118,000,000
Other comprehensive income (loss):
Foreign currency translation adjustments	(1,000,000)	(7,000,000)	10,000,000	(2,000,000)
Financial instruments	8,000,000	5,000,000	6,000,000	1,000,000
Pension and other postretirement benefits	0	0	0	0
Total other comprehensive income (loss)	7,000,000	(2,000,000)	16,000,000	(1,000,000)
Comprehensive income	52,000,000	95,000,000	60,000,000	117,000,000
Preferred dividends			0	0
Comprehensive income (loss) after preferred dividends of subsidiary			60,000,000	117,000,000
Total [Member]
Net income (loss)	102,000,000	719,000,000	802,000,000	1,110,000,000
Other comprehensive income (loss):
Foreign currency translation adjustments	26,000,000	(35,000,000)	86,000,000	49,000,000
Financial instruments	14,000,000	18,000,000	(10,000,000)	(113,000,000)
Pension and other postretirement benefits	7,000,000	2,000,000	10,000,000	4,000,000
Total other comprehensive income (loss)	47,000,000	(15,000,000)	86,000,000	(60,000,000)
Comprehensive income	149,000,000	704,000,000	888,000,000	1,050,000,000
Preferred dividends			(1,000,000)	(1,000,000)
Comprehensive income (loss) after preferred dividends of subsidiary			887,000,000	1,049,000,000
San Diego Gas and Electric Company [Member]
Net income (loss)	(19,000,000)	194,000,000	291,000,000	418,000,000
Other comprehensive income (loss):
Comprehensive income			299,000,000	422,000,000
San Diego Gas and Electric Company [Member] | Pretax amount [Member]
Net income (loss)	(100,000,000)	274,000,000	348,000,000	623,000,000
Other comprehensive income (loss):
Financial instruments	0	0	0	0
Pension and other postretirement benefits	1,000,000		1,000,000
Total other comprehensive income (loss)	1,000,000	0	1,000,000	0
Comprehensive income	(99,000,000)	274,000,000	349,000,000	623,000,000
San Diego Gas and Electric Company [Member] | Income tax (expense) benefit [Member]
Net income (loss)	72,000,000	(91,000,000)	(72,000,000)	(204,000,000)
Other comprehensive income (loss):
Financial instruments	0	0	0	0
Pension and other postretirement benefits	0		0
Total other comprehensive income (loss)	0	0	0	0
Comprehensive income	72,000,000	(91,000,000)	(72,000,000)	(204,000,000)
San Diego Gas and Electric Company [Member] | Net-of-tax amount [Member]
Net income (loss)	(28,000,000)	183,000,000	276,000,000	419,000,000
Other comprehensive income (loss):
Financial instruments	0	0	0	0
Pension and other postretirement benefits	1,000,000		1,000,000
Total other comprehensive income (loss)	1,000,000	0	1,000,000	0
Comprehensive income	(27,000,000)	183,000,000	277,000,000	419,000,000
San Diego Gas and Electric Company [Member] | Noncontrolling Interests (after-tax) [Member]
Net income (loss)	9,000,000	11,000,000	15,000,000	(1,000,000)
Other comprehensive income (loss):
Financial instruments	3,000,000	5,000,000	7,000,000	4,000,000
Pension and other postretirement benefits	0		0
Total other comprehensive income (loss)	3,000,000	5,000,000	7,000,000	4,000,000
Comprehensive income	12,000,000	16,000,000	22,000,000	3,000,000
San Diego Gas and Electric Company [Member] | Total [Member]
Net income (loss)	(19,000,000)	194,000,000	291,000,000	418,000,000
Other comprehensive income (loss):
Financial instruments	3,000,000	5,000,000	7,000,000	4,000,000
Pension and other postretirement benefits	1,000,000		1,000,000
Total other comprehensive income (loss)	4,000,000	5,000,000	8,000,000	4,000,000
Comprehensive income	(15,000,000)	199,000,000	299,000,000	422,000,000
Southern California Gas Company [Member]
Net income (loss)	7,000,000	0	269,000,000	199,000,000
Other comprehensive income (loss):
Comprehensive income			270,000,000	200,000,000
Southern California Gas Company [Member] | Pretax amount [Member]
Net income (loss)	(7,000,000)	21,000,000	372,000,000	274,000,000
Other comprehensive income (loss):
Financial instruments		1,000,000		1,000,000
Pension and other postretirement benefits			1,000,000
Total other comprehensive income (loss)		1,000,000	1,000,000	1,000,000
Comprehensive income	(7,000,000)	22,000,000	373,000,000	275,000,000
Southern California Gas Company [Member] | Income tax (expense) benefit [Member]
Net income (loss)	14,000,000	(21,000,000)	(103,000,000)	(75,000,000)
Other comprehensive income (loss):
Financial instruments		0		0
Pension and other postretirement benefits			0
Total other comprehensive income (loss)		0	0	0
Comprehensive income	14,000,000	(21,000,000)	(103,000,000)	(75,000,000)
Southern California Gas Company [Member] | Net-of-tax amount [Member]
Net income (loss)	7,000,000	0	269,000,000	199,000,000
Other comprehensive income (loss):
Financial instruments		1,000,000		1,000,000
Pension and other postretirement benefits			1,000,000
Total other comprehensive income (loss)		1,000,000	1,000,000	1,000,000
Comprehensive income	$ 7,000,000	$ 1,000,000	$ 270,000,000	$ 200,000,000