OTHER FINANCIAL DATA - PENSION AND OTHER POSTRETIREMENT BENEFITS (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Pension Benefits
Net Periodic Benefit Cost
Service cost	$ 23	$ 28	$ 75	$ 82
Interest cost	39	35	121	111
Expected return on assets	(42)	(39)	(128)	(121)
Amortization of prior service cost	3	1	8	3
Amortization of actuarial loss	3	11	13	41
Settlement	5	1	14	1
Regulatory adjustment	6	(14)	(18)	(65)
Total net periodic benefit cost	37	23	85	52
Pension and Other Postretirement Benefit Contributions [Abstract]
Contributions to pension plans			95
Expected contributions to benefit plans			128
Pension Benefits | San Diego Gas and Electric Company and Subsidiary [Member]
Net Periodic Benefit Cost
Service cost	8	8	23	24
Interest cost	10	9	32	30
Expected return on assets	(13)	(13)	(41)	(39)
Amortization of prior service cost	0	0	1	1
Amortization of actuarial loss	1	3	3	10
Settlement	0	1	2	1
Regulatory adjustment	6	3	7	(3)
Total net periodic benefit cost	12	11	27	24
Pension and Other Postretirement Benefit Contributions [Abstract]
Contributions to pension plans			28
Expected contributions to benefit plans			55
Pension Benefits | Southern California Gas Company [Member]
Net Periodic Benefit Cost
Service cost	13	17	45	50
Interest cost	24	22	75	68
Expected return on assets	(26)	(24)	(78)	(73)
Amortization of prior service cost	2	0	6	1
Amortization of actuarial loss	1	6	5	23
Settlement	4	0	4	0
Regulatory adjustment	0	(17)	(25)	(62)
Total net periodic benefit cost	18	4	32	7
Pension and Other Postretirement Benefit Contributions [Abstract]
Contributions to pension plans			39
Expected contributions to benefit plans			40
Other Postretirement Benefits
Net Periodic Benefit Cost
Service cost	6	8	18	21
Interest cost	13	10	37	33
Expected return on assets	(15)	(15)	(47)	(44)
Amortization of prior service cost	(2)	(1)	(4)	(3)
Amortization of actuarial loss	0	0	0	5
Settlement	5	0	5	0
Regulatory adjustment	5	3	5	7
Total net periodic benefit cost	12	5	14	19
Pension and Other Postretirement Benefit Contributions [Abstract]
Contributions to other postretirement benefit plans			14
Expected contributions to benefit plans			16
Other Postretirement Benefits | San Diego Gas and Electric Company and Subsidiary [Member]
Net Periodic Benefit Cost
Service cost	2	2	5	6
Interest cost	3	2	7	6
Expected return on assets	(2)	(3)	(8)	(7)
Amortization of prior service cost	0	1	2	3
Amortization of actuarial loss	0	0	0	0
Settlement	5	0	5	0
Regulatory adjustment	4	1	1	1
Total net periodic benefit cost	12	3	12	9
Pension and Other Postretirement Benefit Contributions [Abstract]
Contributions to other postretirement benefit plans			12
Expected contributions to benefit plans			14
Other Postretirement Benefits | Southern California Gas Company [Member]
Net Periodic Benefit Cost
Service cost	4	5	12	13
Interest cost	9	8	28	26
Expected return on assets	(12)	(12)	(38)	(36)
Amortization of prior service cost	(2)	(2)	(6)	(6)
Amortization of actuarial loss	0	0	0	4
Settlement	0	0	0	0
Regulatory adjustment	1	2	4	6
Total net periodic benefit cost	0	1	0	7
Pension and Other Postretirement Benefit Contributions [Abstract]
Contributions to other postretirement benefit plans			0
Expected contributions to benefit plans			$ 0