EMPLOYEE BENEFIT PLANS - EMPLOYEE BENEFIT PLANS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Liability, Defined Benefit Plan [Abstract]
Noncurrent liabilities	$ (1,067)	$ (1,143)
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Expected return on plan assets	7.00%
Pension Plan [Member]
CHANGE IN PROJECTED BENEFIT OBLIGATION
Net obligation at January 1	$ 3,339	3,841
Service cost	110	124	$ 117
Interest cost	139	140	150
Contributions from plan participants	0	0
Actuarial loss (gain)	445	(271)
Plan amendments	5	12
Benefit payments	(93)	(113)
Special termination benefits	0	0
Acquisition	0	0
Settlements	(177)	(394)	(194)
Net obligation at December 31	3,768	3,339	3,841
CHANGE IN PLAN ASSETS
Fair value of plan assets at January 1	2,160	2,659
Actual return on plan assets	496	(180)
Employer contributions	276	188
Contributions from plan participants	0	0
Benefit payments	(93)	(113)
Settlements	(177)	(394)
Net recorded (liability) asset at December 31	2,662	2,160	2,659
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Funded status at December 31	(1,106)	(1,179)
Net recorded (liability) asset at December 31	(1,106)	(1,179)
Liability, Defined Benefit Plan [Abstract]
Noncurrent assets	0	0
Current liabilities	(59)	(62)
Noncurrent liabilities	(1,047)	(1,117)
Net recorded (liability) asset	(1,106)	(1,179)
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax [Abstract]
Net actuarial (loss) gain	(113)	(114)
Prior service cost	(14)	(12)
Total	(127)	(126)
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Projected benefit obligation	3,578	3,130
Accumulated benefit obligation	3,229	2,894
Fair value of plan assets	2,662	2,160
NET PERIODIC BENEFIT COST AND AMOUNTS RECOGNIZED IN OCI
Service cost	110	124	117
Interest cost	139	140	150
Expected return on assets	(144)	(157)	(161)
Amortization of Prior service cost (credit)	12	11	11
Amortization of actuarial loss (gain)	36	22	35
Settlement charges	28	66	38
Special termination benefits	0	0	0
Net periodic benefit cost	181	206	190
Regulatory adjustment	77	(30)	(42)
Total expense recognized	258	176	148
CHANGES IN PLAN ASSETS AND BENEFIT OBLIGATIONS RECOGNIZED IN OCI (1)
Net loss (gain)	17	56	0
Prior service cost	5	12	1
Amortization of actuarial loss	(13)	(12)	(10)
Amortization of prior service cost	(3)	(2)	(1)
Settlements	(28)	(12)	(8)
Total recognized in OCI	(22)	42	(18)
Total recognized in net periodic benefit cost and OCI	$ 236	$ 218	$ 130
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Discount rate	3.49%	4.29%
Interest crediting rate	2.28%	3.36%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Discount rate	4.29%	3.64%	4.07%
Expected return on plan assets	7.00%	7.00%	7.00%
Interest crediting rate	3.36%	2.80%	2.86%
EXPECTED CONTRIBUTIONS
Expected employer contributions	$ 268
EXPECTED BENEFIT PAYMENTS
2020	410
2021	263
2022	258
2023	243
2024	239
2025-2029	$ 1,128
Pension Plan [Member] | Maximum [Member]
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Rate of compensation increase	10.00%	10.00%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Rate of compensation increase	10.00%	10.00%	10.00%
Pension Plan [Member] | Minimum [Member]
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Rate of compensation increase	2.70%	2.00%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Rate of compensation increase	2.00%	2.00%	2.00%
Other Postretirement Benefits Plan [Member]
CHANGE IN PROJECTED BENEFIT OBLIGATION
Net obligation at January 1	$ 868	$ 959
Service cost	17	21	$ 21
Interest cost	36	36	39
Contributions from plan participants	21	23
Actuarial loss (gain)	45	(123)
Plan amendments	0	0
Benefit payments	(72)	(74)
Special termination benefits	0	5	18
Acquisition	0	21
Settlements	(2)	0
Net obligation at December 31	913	868	959
CHANGE IN PLAN ASSETS
Fair value of plan assets at January 1	1,108	1,209
Actual return on plan assets	218	(56)
Employer contributions	8	6
Contributions from plan participants	21	23
Benefit payments	(72)	(74)
Settlements	(2)	0
Net recorded (liability) asset at December 31	1,281	1,108	1,209
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Funded status at December 31	368	240
Net recorded (liability) asset at December 31	368	240
Liability, Defined Benefit Plan [Abstract]
Noncurrent assets	391	272
Current liabilities	(3)	(6)
Noncurrent liabilities	(20)	(26)
Net recorded (liability) asset	368	240
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax [Abstract]
Net actuarial (loss) gain	10	8
Prior service cost	0	0
Total	10	8
NET PERIODIC BENEFIT COST AND AMOUNTS RECOGNIZED IN OCI
Service cost	17	21	21
Interest cost	36	36	39
Expected return on assets	(71)	(70)	(66)
Amortization of Prior service cost (credit)	0	1	1
Amortization of actuarial loss (gain)	(10)	(6)	(4)
Settlement charges	0	0	0
Special termination benefits	0	5	18
Net periodic benefit cost	(28)	(13)	9
Regulatory adjustment	29	17	0
Total expense recognized	1	4	9
CHANGES IN PLAN ASSETS AND BENEFIT OBLIGATIONS RECOGNIZED IN OCI (1)
Net loss (gain)	(3)	(4)	(2)
Prior service cost	0	0	0
Amortization of actuarial loss	0	0	0
Amortization of prior service cost	0	0	0
Settlements	0	0	0
Total recognized in OCI	(3)	(4)	(2)
Total recognized in net periodic benefit cost and OCI	$ (2)	$ 0	$ 7
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Discount rate	3.54%	4.29%
Interest crediting rate	2.28%	3.36%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Discount rate	4.29%	3.68%	4.18%
Expected return on plan assets	6.48%	6.49%	6.47%
Interest crediting rate	3.36%	2.80%	2.86%
EXPECTED CONTRIBUTIONS
Expected employer contributions	$ 7
EXPECTED BENEFIT PAYMENTS
2020	50
2021	48
2022	48
2023	48
2024	48
2025-2029	$ 240
Other Postretirement Benefits Plan [Member] | Pre-65Retiree [Member]
ASSUMED HEALTH CARE COST TREND RATES
Health care cost trend rate assumed for next year	6.25%	6.50%	7.00%
Rate to which the cost trend rate is assumed to decline (the ultimate trend)	4.75%	4.75%	5.00%
Other Postretirement Benefits Plan [Member] | Retiree Aged 65 or Older [Member]
ASSUMED HEALTH CARE COST TREND RATES
Health care cost trend rate assumed for next year	4.75%	4.75%	5.00%
Rate to which the cost trend rate is assumed to decline (the ultimate trend)	4.50%	4.50%	4.50%
Other Postretirement Benefits Plan [Member] | Maximum [Member]
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Rate of compensation increase	10.00%	10.00%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Rate of compensation increase	10.00%	10.00%	10.00%
Other Postretirement Benefits Plan [Member] | Minimum [Member]
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Rate of compensation increase	2.70%	2.00%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Rate of compensation increase	2.00%	2.00%	2.00%
San Diego Gas and Electric Company [Member]
Liability, Defined Benefit Plan [Abstract]
Noncurrent liabilities	$ (153)	$ (212)
San Diego Gas and Electric Company [Member] | Pension Plan [Member]
CHANGE IN PROJECTED BENEFIT OBLIGATION
Net obligation at January 1	814	971
Service cost	30	30	$ 29
Interest cost	34	35	38
Contributions from plan participants	0	0
Actuarial loss (gain)	61	(63)
Plan amendments	3	8
Benefit payments	(18)	(22)
Special termination benefits	0	0
Settlements	(39)	(145)
Transfer of liability from other plans	10	0
Net obligation at December 31	895	814	971
CHANGE IN PLAN ASSETS
Fair value of plan assets at January 1	600	776
Actual return on plan assets	135	(56)
Employer contributions	52	47
Contributions from plan participants	0	0
Benefit payments	(18)	(22)
Settlements	(39)	(145)
Transfer of assets from other plans	9	0
Net recorded (liability) asset at December 31	739	600	776
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Funded status at December 31	(156)	(214)
Net recorded (liability) asset at December 31	(156)	(214)
Liability, Defined Benefit Plan [Abstract]
Noncurrent assets	0	0
Current liabilities	(3)	(2)
Noncurrent liabilities	(153)	(212)
Net recorded (liability) asset	(156)	(214)
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax [Abstract]
Net actuarial (loss) gain	(9)	(4)
Prior service cost	(7)	(6)
Total	(16)	(10)
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Projected benefit obligation	861	788
Accumulated benefit obligation	818	762
Fair value of plan assets	739	600
NET PERIODIC BENEFIT COST AND AMOUNTS RECOGNIZED IN OCI
Service cost	30	30	29
Interest cost	34	35	38
Expected return on assets	(38)	(47)	(47)
Amortization of Prior service cost (credit)	3	2	1
Amortization of actuarial loss (gain)	11	1	9
Settlement charges	0	26	0
Special termination benefits	0	0	0
Net periodic benefit cost	40	47	30
Regulatory adjustment	14	(8)	(8)
Total expense recognized	54	39	22
CHANGES IN PLAN ASSETS AND BENEFIT OBLIGATIONS RECOGNIZED IN OCI (1)
Net loss (gain)	5	(1)	2
Prior service cost	2	8	0
Amortization of actuarial loss	0	(1)	(1)
Amortization of prior service cost	(1)	0	0
Settlements	0	(4)	0
Total recognized in OCI	6	2	1
Total recognized in net periodic benefit cost and OCI	$ 60	$ 41	$ 23
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Discount rate	3.44%	4.29%
Interest crediting rate	2.28%	3.36%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Discount rate	4.29%	3.64%	4.08%
Expected return on plan assets	7.00%	7.00%	7.00%
Interest crediting rate	3.36%	2.80%	2.86%
EXPECTED CONTRIBUTIONS
Expected employer contributions	$ 53
EXPECTED BENEFIT PAYMENTS
2020	115
2021	69
2022	64
2023	64
2024	62
2025-2029	$ 283
San Diego Gas and Electric Company [Member] | Pension Plan [Member] | Maximum [Member]
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Rate of compensation increase	10.00%	10.00%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Rate of compensation increase	10.00%	10.00%	10.00%
San Diego Gas and Electric Company [Member] | Pension Plan [Member] | Minimum [Member]
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Rate of compensation increase	2.70%	2.00%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Rate of compensation increase	2.00%	2.00%	2.00%
San Diego Gas and Electric Company [Member] | Other Postretirement Benefits Plan [Member]
CHANGE IN PROJECTED BENEFIT OBLIGATION
Net obligation at January 1	$ 170	$ 185
Service cost	4	5	$ 5
Interest cost	7	7	8
Contributions from plan participants	7	8
Actuarial loss (gain)	7	(17)
Plan amendments	0	0
Benefit payments	(18)	(21)
Special termination benefits	0	3
Settlements	0	0
Transfer of liability from other plans	0	0
Net obligation at December 31	177	170	185
CHANGE IN PLAN ASSETS
Fair value of plan assets at January 1	172	195
Actual return on plan assets	36	(12)
Employer contributions	0	2
Contributions from plan participants	7	8
Benefit payments	(18)	(21)
Settlements	0	0
Transfer of assets from other plans	0	0
Net recorded (liability) asset at December 31	197	172	195
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Funded status at December 31	20	2
Net recorded (liability) asset at December 31	20	2
Liability, Defined Benefit Plan [Abstract]
Noncurrent assets	20	2
Current liabilities	0	0
Noncurrent liabilities	0	0
Net recorded (liability) asset	20	2
NET PERIODIC BENEFIT COST AND AMOUNTS RECOGNIZED IN OCI
Service cost	4	5	5
Interest cost	7	7	8
Expected return on assets	(11)	(13)	(11)
Amortization of Prior service cost (credit)	2	3	3
Amortization of actuarial loss (gain)	(2)	(3)	0
Settlement charges	0	0	0
Special termination benefits	0	3	0
Net periodic benefit cost	0	2	5
Regulatory adjustment	0	0	0
Total expense recognized	0	2	5
CHANGES IN PLAN ASSETS AND BENEFIT OBLIGATIONS RECOGNIZED IN OCI (1)
Net loss (gain)	0	0	0
Prior service cost	0	0	0
Amortization of actuarial loss	0	0	0
Amortization of prior service cost	0	0	0
Settlements	0	0	0
Total recognized in OCI	0	0	0
Total recognized in net periodic benefit cost and OCI	$ 0	$ 2	$ 5
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Discount rate	3.55%	4.30%
Interest crediting rate	2.28%	3.36%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Discount rate	4.30%	3.65%	4.15%
Expected return on plan assets	6.92%	6.94%	6.91%
Interest crediting rate	3.36%	2.80%	2.86%
EXPECTED CONTRIBUTIONS
Expected employer contributions	$ 1
EXPECTED BENEFIT PAYMENTS
2020	10
2021	10
2022	10
2023	10
2024	10
2025-2029	$ 48
San Diego Gas and Electric Company [Member] | Other Postretirement Benefits Plan [Member] | Maximum [Member]
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Rate of compensation increase	10.00%	10.00%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Rate of compensation increase	10.00%	10.00%	10.00%
San Diego Gas and Electric Company [Member] | Other Postretirement Benefits Plan [Member] | Minimum [Member]
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Rate of compensation increase	2.70%	2.00%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Rate of compensation increase	2.00%	2.00%	2.00%
Southern California Gas Company [Member] | Pension Plan [Member]
CHANGE IN PROJECTED BENEFIT OBLIGATION
Net obligation at January 1	$ 2,148	$ 2,486
Service cost	68	81	$ 76
Interest cost	91	92	98
Contributions from plan participants	0	0
Actuarial loss (gain)	345	(215)
Plan amendments	2	0
Benefit payments	(59)	(65)
Special termination benefits	0	0
Settlements	(65)	(231)	(175)
Transfer of liability from other plans	(4)	0
Net obligation at December 31	2,526	2,148	2,486
CHANGE IN PLAN ASSETS
Fair value of plan assets at January 1	1,385	1,694
Actual return on plan assets	320	(117)
Employer contributions	152	104
Contributions from plan participants	0	0
Benefit payments	(59)	(65)
Settlements	(65)	(231)
Transfer of assets from other plans	4	0
Net recorded (liability) asset at December 31	1,737	1,385	1,694
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Funded status at December 31	(789)	(763)
Net recorded (liability) asset at December 31	(789)	(763)
Liability, Defined Benefit Plan [Abstract]
Noncurrent assets	0	0
Current liabilities	(4)	(3)
Noncurrent liabilities	(785)	(760)
Net recorded (liability) asset	(789)	(763)
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax [Abstract]
Net actuarial (loss) gain	(7)	(6)
Prior service cost	(3)	(2)
Total	(10)	(8)
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Projected benefit obligation	2,505	2,123
Accumulated benefit obligation	2,208	1,919
Fair value of plan assets	1,737	1,385
NET PERIODIC BENEFIT COST AND AMOUNTS RECOGNIZED IN OCI
Service cost	68	81	76
Interest cost	91	92	98
Expected return on assets	(94)	(98)	(103)
Amortization of Prior service cost (credit)	8	8	9
Amortization of actuarial loss (gain)	16	13	19
Settlement charges	0	32	30
Special termination benefits	0	0	0
Net periodic benefit cost	89	128	129
Regulatory adjustment	63	(22)	(34)
Total expense recognized	152	106	95
CHANGES IN PLAN ASSETS AND BENEFIT OBLIGATIONS RECOGNIZED IN OCI (1)
Net loss (gain)	2	1	0
Prior service cost	3	0	0
Transfer of actuarial loss	(4)	0	0
Transfer of prior service cost	(1)	0	0
Amortization of actuarial loss	(1)	0	0
Amortization of prior service cost	0	(1)	(1)
Total recognized in OCI	(1)	0	(1)
Total recognized in net periodic benefit cost and OCI	$ 151	$ 106	$ 94
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Discount rate	3.50%	4.30%
Interest crediting rate	2.28%	3.36%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Discount rate	4.30%	3.65%	4.10%
Expected return on plan assets	7.00%	7.00%	7.00%
Interest crediting rate	3.36%	2.80%	2.86%
EXPECTED CONTRIBUTIONS
Expected employer contributions	$ 154
EXPECTED BENEFIT PAYMENTS
2020	229
2021	166
2022	162
2023	156
2024	153
2025-2029	$ 725
Southern California Gas Company [Member] | Pension Plan [Member] | Maximum [Member]
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Rate of compensation increase	10.00%	10.00%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Rate of compensation increase	10.00%	10.00%	10.00%
Southern California Gas Company [Member] | Pension Plan [Member] | Minimum [Member]
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Rate of compensation increase	2.70%	2.00%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Rate of compensation increase	2.00%	2.00%	2.00%
Southern California Gas Company [Member] | Other Postretirement Benefits Plan [Member]
CHANGE IN PROJECTED BENEFIT OBLIGATION
Net obligation at January 1	$ 646	$ 737
Service cost	12	15	$ 14
Interest cost	27	27	29
Contributions from plan participants	13	14
Actuarial loss (gain)	39	(100)
Plan amendments	0	0
Benefit payments	(49)	(49)
Special termination benefits	0	2	18
Settlements	0	0
Transfer of liability from other plans	0	0
Net obligation at December 31	688	646	737
CHANGE IN PLAN ASSETS
Fair value of plan assets at January 1	916	993
Actual return on plan assets	178	(43)
Employer contributions	1	1
Contributions from plan participants	13	14
Benefit payments	(49)	(49)
Settlements	0	0
Transfer of assets from other plans	0	0
Net recorded (liability) asset at December 31	1,059	916	993
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Funded status at December 31	371	270
Net recorded (liability) asset at December 31	371	270
Liability, Defined Benefit Plan [Abstract]
Noncurrent assets	371	270
Current liabilities	0	0
Noncurrent liabilities	0	0
Net recorded (liability) asset	371	270
NET PERIODIC BENEFIT COST AND AMOUNTS RECOGNIZED IN OCI
Service cost	12	15	14
Interest cost	27	27	29
Expected return on assets	(58)	(56)	(53)
Amortization of Prior service cost (credit)	(2)	(3)	(3)
Amortization of actuarial loss (gain)	(8)	(2)	(3)
Settlement charges	0	0	0
Special termination benefits	0	2	18
Net periodic benefit cost	(29)	(17)	2
Regulatory adjustment	29	17	0
Total expense recognized	0	0	2
CHANGES IN PLAN ASSETS AND BENEFIT OBLIGATIONS RECOGNIZED IN OCI (1)
Net loss (gain)	0	0	0
Prior service cost	0	0	0
Transfer of actuarial loss	0	0	0
Transfer of 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	0	0	0
Total recognized in net periodic benefit cost and OCI	$ 0	$ 0	$ 2
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Discount rate	3.55%	4.30%
Interest crediting rate	2.28%	3.36%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Discount rate	4.30%	3.70%	4.20%
Expected return on plan assets	6.38%	6.38%	6.37%
Interest crediting rate	3.36%	2.80%	2.86%
EXPECTED CONTRIBUTIONS
Expected employer contributions	$ 1
EXPECTED BENEFIT PAYMENTS
2020	35
2021	35
2022	35
2023	35
2024	35
2025-2029	$ 176
Southern California Gas Company [Member] | Other Postretirement Benefits Plan [Member] | Maximum [Member]
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Rate of compensation increase	10.00%	10.00%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Rate of compensation increase	10.00%	10.00%	10.00%
Southern California Gas Company [Member] | Other Postretirement Benefits Plan [Member] | Minimum [Member]
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE BENEFIT OBLIGATION
Rate of compensation increase	2.70%	2.00%
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Rate of compensation increase	2.00%	2.00%	2.00%
Unfunded Plan [Member] | Pension Plan [Member]
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Projected benefit obligation	$ 190	$ 209
Accumulated benefit obligation	158	186
Unfunded Plan [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Accumulated benefit obligation	16	22
Unfunded Plan [Member] | San Diego Gas and Electric Company [Member] | Pension Plan [Member]
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Projected benefit obligation	34	26
Accumulated benefit obligation	27	19
Unfunded Plan [Member] | Southern California Gas Company [Member] | Pension Plan [Member]
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Projected benefit obligation	21	25
Accumulated benefit obligation	17	21
Funded Plan [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Accumulated benefit obligation	32	30
Fair value of plan assets	$ 25	$ 20
Risk Mitigating Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Targeted plan asset allocations	26.00%
Risk Mitigating Assets [Member] | Maximum [Member]
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Expected return on plan assets	4.00%
Risk Mitigating Assets [Member] | Minimum [Member]
WEIGHTED-AVERAGE ASSUMPTIONS USED TO DETERMINE NET PERIODIC BENEFIT COST
Expected return on plan assets	1.00%
Risk Mitigating Assets [Member] | San Diego Gas and Electric Company [Member]
EXPECTED BENEFIT PAYMENTS
Asset allocations	62.00%
Risk Mitigating Assets [Member] | Southern California Gas Company [Member]
Defined Benefit Plan Disclosure [Line Items]
Targeted plan asset allocations	75.00%
EXPECTED BENEFIT PAYMENTS
Asset allocations	62.00%
Long Credit [Member]
Defined Benefit Plan Disclosure [Line Items]
Targeted plan asset allocations	18.00%