EMPLOYEE BENEFIT PLANS - EMPLOYEE BENEFIT PLANS (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016		Dec. 31, 2015
Liability, Defined Benefit Plan [Abstract]
Noncurrent liabilities	$ (1,148,000,000)	$ (1,208,000,000)	[1]
Defined Benefit Plan, Expected Amortization, Next Fiscal Year [Abstract]
Net actuarial gain (loss) expected to be amortized next year	(10,000,000)
Prior service cost (credit) expected to be amortized next year	$ 1,000,000
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Expected return on plan assets	7.00%
Pension Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	$ 3,679,000,000	3,649,000,000
Service cost	117,000,000	107,000,000		$ 114,000,000
Interest cost	151,000,000	160,000,000		154,000,000
Contributions from plan participants	0	0
Actuarial loss (gain)	286,000,000	116,000,000
Benefit payments	(182,000,000)	(217,000,000)
Divestiture of EnergySouth	0	(61,000,000)
Plan amendments	1,000,000	0
Special termination benefits	0	0
Curtailments	(1,000,000)	0
Settlements	(194,000,000)	(75,000,000)
Ending balance	3,857,000,000	3,679,000,000		3,649,000,000
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	2,459,000,000	2,484,000,000
Actual return on plan assets	421,000,000	207,000,000
Employer contributions	155,000,000	104,000,000
Contributions from plan participants	0	0
Benefit payments	(182,000,000)	(217,000,000)
Divestiture of EnergySouth	0	(44,000,000)
Settlements	(194,000,000)	(75,000,000)
Ending balance	2,659,000,000	2,459,000,000		2,484,000,000
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Funded status	(1,198,000,000)	(1,220,000,000)
Net recorded liability	(1,198,000,000)	(1,220,000,000)
Liability, Defined Benefit Plan [Abstract]
Noncurrent assets	0	0
Current liabilities	(69,000,000)	(56,000,000)
Noncurrent liabilities	(1,129,000,000)	(1,164,000,000)
Net recorded (liability) asset	(1,198,000,000)	(1,220,000,000)
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax [Abstract]
Net actuarial (loss) gain	(84,000,000)	(95,000,000)
Prior service cost	(4,000,000)	(4,000,000)
Total	(88,000,000)	(99,000,000)
Accumulated benefit obligation	3,551,000,000	3,465,000,000
Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Projected benefit obligation	3,623,000,000	3,431,000,000
Accumulated benefit obligation	3,334,000,000	3,227,000,000
Fair value of plan assets	2,659,000,000	2,459,000,000
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	117,000,000	107,000,000		114,000,000
Interest cost	151,000,000	160,000,000		154,000,000
Expected return on assets	(161,000,000)	(166,000,000)		(173,000,000)
Amortization of Prior service cost (credit)	11,000,000	11,000,000		11,000,000
Amortization of actuarial loss (gain)	36,000,000	30,000,000		38,000,000
Settlement and curtailment charges	38,000,000	16,000,000		4,000,000
Settlement charge	38,000,000	16,000,000
Special termination benefits	0	0		0
Regulatory adjustment	(42,000,000)	(57,000,000)		(110,000,000)
Defined Benefit Plan, Net Periodic Benefit Cost, Total	150,000,000	101,000,000		38,000,000
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax [Abstract]
Net loss (gain)	0	26,000,000		17,000,000
Prior service cost	1,000,000	0		4,000,000
Amortization of actuarial loss	(18,000,000)	(10,000,000)		(14,000,000)
Amortization of prior service cost	(1,000,000)	(1,000,000)		0
Total recognized in OCI	(18,000,000)	15,000,000		7,000,000
Total recognized in net periodic benefit cost and OCI	$ 132,000,000	$ 116,000,000		$ 45,000,000
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	3.65%	4.08%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	4.08%	4.46%		4.09%
Expected return on plan assets	7.00%	7.00%		7.00%
Defined Benefit Plan, Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rate [Abstract]
Expected employer contributions	$ 226,000,000
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2018	351,000,000
2019	304,000,000
2020	294,000,000
2021	285,000,000
2022	273,000,000
2023-2027	$ 1,217,000,000
Pension Plan [Member] | Maximum [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Rate of compensation increase	10.00%	10.00%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Rate of compensation increase	10.00%	10.00%		10.00%
Pension Plan [Member] | Minimum [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Rate of compensation increase	2.00%	2.00%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Rate of compensation increase	2.00%	2.00%		2.00%
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	$ 922,000,000	$ 963,000,000
Service cost	21,000,000	20,000,000		$ 26,000,000
Interest cost	39,000,000	42,000,000		44,000,000
Contributions from plan participants	20,000,000	20,000,000
Actuarial loss (gain)	6,000,000	(81,000,000)
Benefit payments	(63,000,000)	(61,000,000)
Divestiture of EnergySouth	0	(6,000,000)
Plan amendments	0	0
Special termination benefits	18,000,000	26,000,000
Curtailments	0	0
Settlements	0	(1,000,000)
Ending balance	963,000,000	922,000,000		963,000,000
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	1,057,000,000	1,003,000,000
Actual return on plan assets	185,000,000	94,000,000
Employer contributions	10,000,000	6,000,000
Contributions from plan participants	20,000,000	20,000,000
Benefit payments	(63,000,000)	(61,000,000)
Divestiture of EnergySouth	0	(4,000,000)
Settlements	0	(1,000,000)
Ending balance	1,209,000,000	1,057,000,000		1,003,000,000
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Funded status	246,000,000	135,000,000
Net recorded liability	246,000,000	135,000,000
Liability, Defined Benefit Plan [Abstract]
Noncurrent assets	266,000,000	179,000,000
Current liabilities	(1,000,000)	0
Noncurrent liabilities	(19,000,000)	(44,000,000)
Net recorded (liability) asset	246,000,000	135,000,000
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax [Abstract]
Net actuarial (loss) gain	4,000,000	3,000,000
Prior service cost	0	0
Total	4,000,000	3,000,000
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	21,000,000	20,000,000		26,000,000
Interest cost	39,000,000	42,000,000		44,000,000
Expected return on assets	(66,000,000)	(69,000,000)		(68,000,000)
Amortization of Prior service cost (credit)	1,000,000	0		(4,000,000)
Amortization of actuarial loss (gain)	(4,000,000)	(1,000,000)		0
Settlement and curtailment charges	0	0		0
Special termination benefits	18,000,000	26,000,000		0
Regulatory adjustment	0	(11,000,000)		12,000,000
Defined Benefit Plan, Net Periodic Benefit Cost, Total	9,000,000	7,000,000		10,000,000
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax [Abstract]
Net loss (gain)	(2,000,000)	(2,000,000)		(4,000,000)
Prior service cost	0	0		0
Amortization of actuarial loss	0	0		0
Amortization of prior service cost	0	0		0
Total recognized in OCI	(2,000,000)	(2,000,000)		(4,000,000)
Total recognized in net periodic benefit cost and OCI	$ 7,000,000	$ 5,000,000		$ 6,000,000
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	3.70%	4.19%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	4.19%	4.49%		4.15%
Expected return on plan assets	6.47%	6.98%		6.98%
Defined Benefit Plan, Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rate [Abstract]
Effect of 1% increase on total of service and interest cost components of net periodic postretirement health care benefit cost	$ 5,000,000
Effect of 1% decrease on total of service and interest cost components of net periodic postretirement health care benefit cost	(4,000,000)
Effect of 1% increase on the health care component of the accumulated other postretirement benefit obligations	53,000,000
Effect of 1% decrease on the health care component of the accumulated other postretirement benefit obligations	(44,000,000)
Expected employer contributions	9,000,000
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2018	52,000,000
2019	52,000,000
2020	54,000,000
2021	53,000,000
2022	53,000,000
2023-2027	$ 262,000,000
Other Postretirement Benefits Plan [Member] | Pre-65Retiree [Member]
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]
Health care cost trend rate assumed for next year	7.00%	8.00%		8.10%
Rate to which the cost trend rate is assumed to decline (the ultimate trend)	5.00%	5.00%		5.00%
Year the rate reaches the ultimate trend	2022	2022		2022
Other Postretirement Benefits Plan [Member] | Retiree Aged 65 or Older [Member]
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]
Health care cost trend rate assumed for next year	5.00%	5.50%		5.50%
Rate to which the cost trend rate is assumed to decline (the ultimate trend)	4.50%	4.50%		4.50%
Year the rate reaches the ultimate trend	2022	2022		2022
Other Postretirement Benefits Plan [Member] | Maximum [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Rate of compensation increase	10.00%	10.00%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Rate of compensation increase	10.00%	10.00%		10.00%
Other Postretirement Benefits Plan [Member] | Minimum [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Rate of compensation increase	2.00%	2.00%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Rate of compensation increase	2.00%	2.00%		2.00%
Southern California Gas Company [Member]
Defined Benefit Plan, Expected Amortization, Next Fiscal Year [Abstract]
Net actuarial gain (loss) expected to be amortized next year	$ (1,000,000)
Prior service cost (credit) expected to be amortized next year	1,000,000
Southern California Gas Company [Member] | Pension Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	2,343,000,000	$ 2,255,000,000
Service cost	76,000,000	67,000,000		$ 74,000,000
Interest cost	98,000,000	101,000,000		98,000,000
Contributions from plan participants	0	0
Actuarial loss (gain)	216,000,000	77,000,000
Benefit payments	(73,000,000)	(158,000,000)
Special termination benefits	0	0
Settlements	(175,000,000)	0
Transfer of liability from (to) other plans	1,000,000	1,000,000
Ending balance	2,486,000,000	2,343,000,000		2,255,000,000
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	1,579,000,000	1,537,000,000
Actual return on plan assets	269,000,000	128,000,000
Employer contributions	93,000,000	72,000,000
Contributions from plan participants	0	0
Benefit payments	(73,000,000)	(158,000,000)
Transfer of assets from other plans	1,000,000	0
Settlements	(175,000,000)	0
Ending balance	1,694,000,000	1,579,000,000		1,537,000,000
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Funded status	(792,000,000)	(764,000,000)
Net recorded liability	(792,000,000)	(764,000,000)
Liability, Defined Benefit Plan [Abstract]
Noncurrent assets	0	0
Current liabilities	(3,000,000)	(2,000,000)
Noncurrent liabilities	(789,000,000)	(762,000,000)
Net recorded (liability) asset	(792,000,000)	(764,000,000)
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax [Abstract]
Net actuarial (loss) gain	(6,000,000)	(6,000,000)
Prior service cost	(2,000,000)	(3,000,000)
Total	(8,000,000)	(9,000,000)
Accumulated benefit obligation	2,241,000,000	2,167,000,000
Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Projected benefit obligation	2,462,000,000	2,320,000,000
Accumulated benefit obligation	2,220,000,000	2,148,000,000
Fair value of plan assets	1,694,000,000	1,579,000,000
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	76,000,000	67,000,000		74,000,000
Interest cost	98,000,000	101,000,000		98,000,000
Expected return on assets	(103,000,000)	(103,000,000)		(106,000,000)
Amortization of Prior service cost (credit)	9,000,000	9,000,000		9,000,000
Amortization of actuarial loss (gain)	19,000,000	11,000,000		21,000,000
Settlement charge	30,000,000	0		0
Special termination benefits	0	0		0
Regulatory adjustment	(34,000,000)	(12,000,000)		(90,000,000)
Defined Benefit Plan, Net Periodic Benefit Cost, Total	95,000,000	73,000,000		6,000,000
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax [Abstract]
Net loss (gain)	0	4,000,000		0
Prior service cost	0	2,000,000		2,000,000
Amortization of prior service cost	(1,000,000)	0		0
Total recognized in OCI	(1,000,000)	6,000,000		2,000,000
Total recognized in net periodic benefit cost and OCI	$ 94,000,000	$ 79,000,000		$ 8,000,000
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	3.65%	4.10%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	4.10%	4.50%		4.15%
Expected return on plan assets	7.00%	7.00%		7.00%
Defined Benefit Plan, Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rate [Abstract]
Expected employer contributions	$ 113,000,000
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2018	192,000,000
2019	188,000,000
2020	179,000,000
2021	173,000,000
2022	172,000,000
2023-2027	$ 782,000,000
Southern California Gas Company [Member] | Pension Plan [Member] | Maximum [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Rate of compensation increase	10.00%	10.00%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Rate of compensation increase	10.00%	10.00%		10.00%
Southern California Gas Company [Member] | Pension Plan [Member] | Minimum [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Rate of compensation increase	2.00%	2.00%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Rate of compensation increase	2.00%	2.00%		2.00%
Southern California Gas Company [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	$ 691,000,000	$ 752,000,000
Service cost	14,000,000	14,000,000		$ 17,000,000
Interest cost	29,000,000	32,000,000		34,000,000
Contributions from plan participants	13,000,000	13,000,000
Actuarial loss (gain)	16,000,000	(86,000,000)
Benefit payments	(44,000,000)	(45,000,000)
Special termination benefits	18,000,000	11,000,000
Settlements	0	0
Transfer of liability from (to) other plans	0	0
Ending balance	737,000,000	691,000,000		752,000,000
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	870,000,000	822,000,000
Actual return on plan assets	151,000,000	79,000,000
Employer contributions	3,000,000	1,000,000
Contributions from plan participants	13,000,000	13,000,000
Benefit payments	(44,000,000)	(45,000,000)
Transfer of assets from other plans	0	0
Settlements	0	0
Ending balance	993,000,000	870,000,000		822,000,000
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Funded status	256,000,000	179,000,000
Net recorded liability	256,000,000	179,000,000
Liability, Defined Benefit Plan [Abstract]
Noncurrent assets	256,000,000	179,000,000
Current liabilities	0	0
Noncurrent liabilities	0	0
Net recorded (liability) asset	256,000,000	179,000,000
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	14,000,000	14,000,000		17,000,000
Interest cost	29,000,000	32,000,000		34,000,000
Expected return on assets	(53,000,000)	(56,000,000)		(56,000,000)
Amortization of Prior service cost (credit)	(3,000,000)	(4,000,000)		(7,000,000)
Amortization of actuarial loss (gain)	(3,000,000)	0		0
Settlement charge	0	0		0
Special termination benefits	18,000,000	11,000,000		0
Regulatory adjustment	0	3,000,000		12,000,000
Defined Benefit Plan, Net Periodic Benefit Cost, Total	2,000,000	0		0
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax [Abstract]
Net loss (gain)	0	0		0
Prior service cost	0	0		0
Amortization of prior service cost	0	0		0
Total recognized in OCI	0	0		0
Total recognized in net periodic benefit cost and OCI	$ 2,000,000	$ 0		$ 0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	3.70%	4.20%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	4.20%	4.50%		4.15%
Expected return on plan assets	6.37%	7.00%		7.00%
Defined Benefit Plan, Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rate [Abstract]
Effect of 1% increase on total of service and interest cost components of net periodic postretirement health care benefit cost	$ 4,000,000
Effect of 1% decrease on total of service and interest cost components of net periodic postretirement health care benefit cost	(3,000,000)
Effect of 1% increase on the health care component of the accumulated other postretirement benefit obligations	48,000,000
Effect of 1% decrease on the health care component of the accumulated other postretirement benefit obligations	(40,000,000)
Expected employer contributions	2,000,000
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2018	38,000,000
2019	39,000,000
2020	40,000,000
2021	40,000,000
2022	40,000,000
2023-2027	$ 197,000,000
Southern California Gas Company [Member] | Other Postretirement Benefits Plan [Member] | Maximum [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Rate of compensation increase	10.00%	10.00%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Rate of compensation increase	10.00%	10.00%		10.00%
Southern California Gas Company [Member] | Other Postretirement Benefits Plan [Member] | Minimum [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Rate of compensation increase	2.00%	2.00%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Rate of compensation increase	2.00%	2.00%		2.00%
San Diego Gas and Electric Company [Member]
Liability, Defined Benefit Plan [Abstract]
Noncurrent liabilities	$ (182,000,000)	$ (232,000,000)	[1]
Defined Benefit Plan, Expected Amortization, Next Fiscal Year [Abstract]
Net actuarial gain (loss) expected to be amortized next year	(1,000,000)
Prior service cost (credit) expected to be amortized next year	0
San Diego Gas and Electric Company [Member] | Pension Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	935,000,000	965,000,000
Service cost	29,000,000	29,000,000		$ 29,000,000
Interest cost	38,000,000	41,000,000		39,000,000
Contributions from plan participants	0	0
Actuarial loss (gain)	50,000,000	7,000,000
Benefit payments	(83,000,000)	(25,000,000)
Special termination benefits	0	0
Settlements	0	(75,000,000)
Transfer of liability from (to) other plans	2,000,000	(7,000,000)
Ending balance	971,000,000	935,000,000		965,000,000
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	714,000,000	752,000,000
Actual return on plan assets	120,000,000	59,000,000
Employer contributions	22,000,000	3,000,000
Contributions from plan participants	0	0
Benefit payments	(83,000,000)	(25,000,000)
Transfer of assets from other plans	3,000,000	0
Settlements	0	(75,000,000)
Ending balance	776,000,000	714,000,000		752,000,000
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Funded status	(195,000,000)	(221,000,000)
Net recorded liability	(195,000,000)	(221,000,000)
Liability, Defined Benefit Plan [Abstract]
Noncurrent assets	0	0
Current liabilities	(13,000,000)	(10,000,000)
Noncurrent liabilities	(182,000,000)	(211,000,000)
Net recorded (liability) asset	(195,000,000)	(221,000,000)
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax [Abstract]
Net actuarial (loss) gain	(8,000,000)	(8,000,000)
Accumulated benefit obligation	930,000,000	904,000,000
Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Projected benefit obligation	939,000,000	902,000,000
Accumulated benefit obligation	900,000,000	874,000,000
Fair value of plan assets	776,000,000	714,000,000
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	29,000,000	29,000,000		29,000,000
Interest cost	38,000,000	41,000,000		39,000,000
Expected return on assets	(47,000,000)	(49,000,000)		(54,000,000)
Amortization of Prior service cost (credit)	1,000,000	1,000,000		8,000,000
Amortization of actuarial loss (gain)	9,000,000	10,000,000		2,000,000
Settlement charge	0	16,000,000		0
Special termination benefits	0	0		0
Regulatory adjustment	(8,000,000)	(45,000,000)		(20,000,000)
Defined Benefit Plan, Net Periodic Benefit Cost, Total	22,000,000	3,000,000		4,000,000
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax [Abstract]
Net loss (gain)	2,000,000	1,000,000		(6,000,000)
Amortization of actuarial loss	(1,000,000)	(1,000,000)		(1,000,000)
Total recognized in OCI	1,000,000	0		(7,000,000)
Total recognized in net periodic benefit cost and OCI	$ 23,000,000	$ 3,000,000		$ (3,000,000)
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	3.64%	4.08%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	4.08%	4.35%		4.00%
Expected return on plan assets	7.00%	7.00%		7.00%
Defined Benefit Plan, Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rate [Abstract]
Expected employer contributions	$ 48,000,000
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2018	90,000,000
2019	76,000,000
2020	74,000,000
2021	71,000,000
2022	68,000,000
2023-2027	$ 314,000,000
San Diego Gas and Electric Company [Member] | Pension Plan [Member] | Maximum [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Rate of compensation increase	10.00%	10.00%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Rate of compensation increase	10.00%	10.00%		10.00%
San Diego Gas and Electric Company [Member] | Pension Plan [Member] | Minimum [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Rate of compensation increase	2.00%	2.00%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Rate of compensation increase	2.00%	2.00%		2.00%
San Diego Gas and Electric Company [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	$ 190,000,000	$ 165,000,000
Service cost	5,000,000	5,000,000		$ 7,000,000
Interest cost	8,000,000	7,000,000		8,000,000
Contributions from plan participants	7,000,000	7,000,000
Actuarial loss (gain)	(9,000,000)	6,000,000
Benefit payments	(16,000,000)	(14,000,000)
Special termination benefits	0	14,000,000
Settlements	0	0
Transfer of liability from (to) other plans	0	0
Ending balance	185,000,000	190,000,000		165,000,000
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	169,000,000	161,000,000
Actual return on plan assets	30,000,000	13,000,000
Employer contributions	5,000,000	2,000,000
Contributions from plan participants	7,000,000	7,000,000
Benefit payments	(16,000,000)	(14,000,000)
Transfer of assets from other plans	0	0
Settlements	0	0
Ending balance	195,000,000	169,000,000		161,000,000
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Funded status	10,000,000	(21,000,000)
Net recorded liability	10,000,000	(21,000,000)
Liability, Defined Benefit Plan [Abstract]
Noncurrent assets	10,000,000	0
Current liabilities	0	0
Noncurrent liabilities	0	(21,000,000)
Net recorded (liability) asset	10,000,000	(21,000,000)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	5,000,000	5,000,000		7,000,000
Interest cost	8,000,000	7,000,000		8,000,000
Expected return on assets	(11,000,000)	(12,000,000)		(11,000,000)
Amortization of Prior service cost (credit)	3,000,000	3,000,000		3,000,000
Amortization of actuarial loss (gain)	0	(1,000,000)		0
Settlement charge	0	0		0
Special termination benefits	0	14,000,000		0
Regulatory adjustment	0	(14,000,000)		0
Defined Benefit Plan, Net Periodic Benefit Cost, Total	5,000,000	2,000,000		7,000,000
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax [Abstract]
Net loss (gain)	0	0		0
Amortization of actuarial loss	0	0		0
Total recognized in OCI	0	0		0
Total recognized in net periodic benefit cost and OCI	$ 5,000,000	$ 2,000,000		$ 7,000,000
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	3.65%	4.15%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	4.15%	4.50%		4.15%
Expected return on plan assets	6.91%	6.90%		6.91%
Defined Benefit Plan, Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rate [Abstract]
Effect of 1% increase on total of service and interest cost components of net periodic postretirement health care benefit cost	$ 1,000,000
Effect of 1% decrease on total of service and interest cost components of net periodic postretirement health care benefit cost	0
Effect of 1% increase on the health care component of the accumulated other postretirement benefit obligations	3,000,000
Effect of 1% decrease on the health care component of the accumulated other postretirement benefit obligations	(2,000,000)
Expected employer contributions	3,000,000
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2018	10,000,000
2019	10,000,000
2020	10,000,000
2021	11,000,000
2022	11,000,000
2023-2027	$ 52,000,000
San Diego Gas and Electric Company [Member] | Other Postretirement Benefits Plan [Member] | Maximum [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Rate of compensation increase	10.00%	10.00%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Rate of compensation increase	10.00%	10.00%		10.00%
San Diego Gas and Electric Company [Member] | Other Postretirement Benefits Plan [Member] | Minimum [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Rate of compensation increase	2.00%	2.00%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Rate of compensation increase	2.00%	2.00%		2.00%
Mobile Gas [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]
Health care cost trend rate assumed for next year				8.10%
Rate to which the cost trend rate is assumed to decline (the ultimate trend)				5.00%
Year the rate reaches the ultimate trend				2022
Chilquinta Energia [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]
Health care cost trend rate assumed for next year	3.00%	3.00%		3.00%
Rate to which the cost trend rate is assumed to decline (the ultimate trend)	3.00%	3.00%		3.00%

[1] Reflects reclassifications to conform to current year presentation, which we discuss in Note 1.