FAIR VALUE MEASUREMENTS 2 (Details) - USD ($) $ in Millions		Sep. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Nuclear decommissioning trusts - equity securities		$ 588	$ 655
Nuclear decommissioning trusts - Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies		95	109
Nuclear decomissioning trusts - Municipal debt securities		154	129
Nuclear decommissioning trusts - Other debt securities		205	207
Nuclear decommissioning trusts - Total debt securities		454	445
Total nuclear decommissioning trusts	[1]	1,042	1,100
Interest rate instruments, assets		7	48
Commodity contracts not subject to rate recovery, assets		51	33
Commodity contracts subject to rate recovery, assets		107	122
Total fair value of assets measured on a recurring basis		1,207	1,303
Interest rate instruments, liabilities		178	155
Commodity contracts not subject to rate recovery, liabilities		7	8
Commodity contracts subject to rate recovery, liabilities		69	16
Total fair value of liabilities measured on a recurring basis		254	179
San Diego Gas and Electric Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Nuclear decommissioning trusts - equity securities		588	655
Nuclear decommissioning trusts - Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies		95	109
Nuclear decomissioning trusts - Municipal debt securities		154	129
Nuclear decommissioning trusts - Other debt securities		205	207
Nuclear decommissioning trusts - Total debt securities		454	445
Total nuclear decommissioning trusts	[1]	1,042	1,100
Commodity contracts not subject to rate recovery, assets		1
Commodity contracts subject to rate recovery, assets		105	119
Total fair value of assets measured on a recurring basis		1,148	1,219
Interest rate instruments, liabilities		44	47
Commodity contracts not subject to rate recovery, liabilities		0	0
Commodity contracts subject to rate recovery, liabilities		69	15
Total fair value of liabilities measured on a recurring basis		113	62
Southern California Gas Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commodity contracts not subject to rate recovery, assets		1
Commodity contracts subject to rate recovery, assets		2	3
Total fair value of assets measured on a recurring basis		3	3
Commodity contracts not subject to rate recovery, liabilities		0	0
Commodity contracts subject to rate recovery, liabilities			1
Total fair value of liabilities measured on a recurring basis		0	1
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Nuclear decommissioning trusts - equity securities		588	655
Nuclear decommissioning trusts - Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies		51	62
Nuclear decomissioning trusts - Municipal debt securities		0	0
Nuclear decommissioning trusts - Other debt securities		0	0
Nuclear decommissioning trusts - Total debt securities		51	62
Total nuclear decommissioning trusts	[1]	639	717
Interest rate instruments, assets		0	0
Commodity contracts not subject to rate recovery, assets		31	28
Commodity contracts subject to rate recovery, assets		0	0
Total fair value of assets measured on a recurring basis		670	745
Interest rate instruments, liabilities		0	0
Commodity contracts not subject to rate recovery, liabilities		8	3
Commodity contracts subject to rate recovery, liabilities		0	0
Total fair value of liabilities measured on a recurring basis		8	3
Level 1 | San Diego Gas and Electric Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Nuclear decommissioning trusts - equity securities		588	655
Nuclear decommissioning trusts - Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies		51	62
Nuclear decomissioning trusts - Municipal debt securities		0	0
Nuclear decommissioning trusts - Other debt securities		0	0
Nuclear decommissioning trusts - Total debt securities		51	62
Total nuclear decommissioning trusts	[1]	639	717
Commodity contracts not subject to rate recovery, assets		0
Commodity contracts subject to rate recovery, assets		0	0
Total fair value of assets measured on a recurring basis		639	717
Interest rate instruments, liabilities		0	0
Commodity contracts not subject to rate recovery, liabilities		1	1
Commodity contracts subject to rate recovery, liabilities		0	0
Total fair value of liabilities measured on a recurring basis		1	1
Level 1 | Southern California Gas Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commodity contracts not subject to rate recovery, assets		0
Commodity contracts subject to rate recovery, assets		0	0
Total fair value of assets measured on a recurring basis		0	0
Commodity contracts not subject to rate recovery, liabilities		2	2
Commodity contracts subject to rate recovery, liabilities			0
Total fair value of liabilities measured on a recurring basis		2	2
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Nuclear decommissioning trusts - equity securities		0	0
Nuclear decommissioning trusts - Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies		44	47
Nuclear decomissioning trusts - Municipal debt securities		154	129
Nuclear decommissioning trusts - Other debt securities		205	207
Nuclear decommissioning trusts - Total debt securities		403	383
Total nuclear decommissioning trusts	[1]	403	383
Interest rate instruments, assets		7	48
Commodity contracts not subject to rate recovery, assets		17	16
Commodity contracts subject to rate recovery, assets		1	1
Total fair value of assets measured on a recurring basis		428	448
Interest rate instruments, liabilities		178	155
Commodity contracts not subject to rate recovery, liabilities		2	9
Commodity contracts subject to rate recovery, liabilities		67	52
Total fair value of liabilities measured on a recurring basis		247	216
Level 2 | San Diego Gas and Electric Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Nuclear decommissioning trusts - equity securities		0	0
Nuclear decommissioning trusts - Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies		44	47
Nuclear decomissioning trusts - Municipal debt securities		154	129
Nuclear decommissioning trusts - Other debt securities		205	207
Nuclear decommissioning trusts - Total debt securities		403	383
Total nuclear decommissioning trusts	[1]	403	383
Commodity contracts not subject to rate recovery, assets		0
Commodity contracts subject to rate recovery, assets		0	0
Total fair value of assets measured on a recurring basis		403	383
Interest rate instruments, liabilities		44	47
Commodity contracts not subject to rate recovery, liabilities		0	0
Commodity contracts subject to rate recovery, liabilities		67	51
Total fair value of liabilities measured on a recurring basis		111	98
Level 2 | Southern California Gas Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commodity contracts not subject to rate recovery, assets		0
Commodity contracts subject to rate recovery, assets		1	1
Total fair value of assets measured on a recurring basis		1	1
Commodity contracts not subject to rate recovery, liabilities		0	0
Commodity contracts subject to rate recovery, liabilities			1
Total fair value of liabilities measured on a recurring basis		0	1
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Nuclear decommissioning trusts - equity securities		0	0
Nuclear decommissioning trusts - Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies		0	0
Nuclear decomissioning trusts - Municipal debt securities		0	0
Nuclear decommissioning trusts - Other debt securities		0	0
Nuclear decommissioning trusts - Total debt securities		0	0
Total nuclear decommissioning trusts	[1]	0	0
Interest rate instruments, assets		0	0
Commodity contracts not subject to rate recovery, assets		0	0
Commodity contracts subject to rate recovery, assets		91	107
Total fair value of assets measured on a recurring basis		91	107
Interest rate instruments, liabilities		0	0
Commodity contracts not subject to rate recovery, liabilities		0	0
Commodity contracts subject to rate recovery, liabilities		55	0
Total fair value of liabilities measured on a recurring basis		55	0
Level 3 | San Diego Gas and Electric Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Nuclear decommissioning trusts - equity securities		0	0
Nuclear decommissioning trusts - Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies		0	0
Nuclear decomissioning trusts - Municipal debt securities		0	0
Nuclear decommissioning trusts - Other debt securities		0	0
Nuclear decommissioning trusts - Total debt securities		0	0
Total nuclear decommissioning trusts	[1]	0	0
Commodity contracts not subject to rate recovery, assets		0
Commodity contracts subject to rate recovery, assets		91	107
Total fair value of assets measured on a recurring basis		91	107
Interest rate instruments, liabilities		0	0
Commodity contracts not subject to rate recovery, liabilities		0	0
Commodity contracts subject to rate recovery, liabilities		55	0
Total fair value of liabilities measured on a recurring basis		55	0
Level 3 | Southern California Gas Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commodity contracts not subject to rate recovery, assets		0
Commodity contracts subject to rate recovery, assets		0	0
Total fair value of assets measured on a recurring basis		0	0
Commodity contracts not subject to rate recovery, liabilities		0	0
Commodity contracts subject to rate recovery, liabilities			0
Total fair value of liabilities measured on a recurring basis		0	0
Collateral Netted [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Nuclear decommissioning trusts - equity securities	[2]	0	0
Nuclear decommissioning trusts - Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies	[2]	0	0
Nuclear decomissioning trusts - Municipal debt securities	[2]	0	0
Nuclear decommissioning trusts - Other debt securities	[2]	0	0
Nuclear decommissioning trusts - Total debt securities	[2]	0	0
Total nuclear decommissioning trusts	[1],[2]	0	0
Interest rate instruments, assets	[2]	0	0
Commodity contracts not subject to rate recovery, assets	[2]	3	(11)
Commodity contracts subject to rate recovery, assets	[2]	15	14
Total fair value of assets measured on a recurring basis	[2]	18	3
Interest rate instruments, liabilities	[2]	0	0
Commodity contracts not subject to rate recovery, liabilities	[2]	(3)	(4)
Commodity contracts subject to rate recovery, liabilities	[2]	(53)	(36)
Total fair value of liabilities measured on a recurring basis	[2]	(56)	(40)
Collateral Netted [Member] | San Diego Gas and Electric Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Nuclear decommissioning trusts - equity securities	[2]	0	0
Nuclear decommissioning trusts - Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies	[2]	0	0
Nuclear decomissioning trusts - Municipal debt securities	[2]	0	0
Nuclear decommissioning trusts - Other debt securities	[2]	0	0
Nuclear decommissioning trusts - Total debt securities	[2]	0	0
Total nuclear decommissioning trusts	[1],[2]	0	0
Commodity contracts not subject to rate recovery, assets	[2]	1
Commodity contracts subject to rate recovery, assets	[2]	14	12
Total fair value of assets measured on a recurring basis	[2]	15	12
Interest rate instruments, liabilities	[2]	0	0
Commodity contracts not subject to rate recovery, liabilities	[2]	(1)	(1)
Commodity contracts subject to rate recovery, liabilities	[2]	(53)	(36)
Total fair value of liabilities measured on a recurring basis	[2]	(54)	(37)
Collateral Netted [Member] | Southern California Gas Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commodity contracts not subject to rate recovery, assets	[2]	1
Commodity contracts subject to rate recovery, assets	[2]	1	2
Total fair value of assets measured on a recurring basis	[2]	2	2
Commodity contracts not subject to rate recovery, liabilities	[2]	(2)	(2)
Commodity contracts subject to rate recovery, liabilities	[2]		0
Total fair value of liabilities measured on a recurring basis	[2]	$ (2)	$ (2)

[1] Excludes cash balances and cash equivalents.

[2] Includes the effect of the contractual ability to settle contracts under master netting agreements and with cash collateral, as well as cash collateral not offset.