FAIR VALUE MEASUREMENTS 3 (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013		Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Nuclear decommissioning trusts - equity securities	$ 599		$ 539
Nuclear decommissioning trusts - Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies	133		156
Nuclear decomissioning trusts - Municipal debt securities	104		63
Nuclear decommissioning trusts - Other debt securities	134		130
Nuclear decommissioning trusts - Total debt securities	371		349
Total nuclear decommissioning trusts	970	[1]	888	[1]
Interest rate instruments, assets	63		68
Commodity contracts subject to rate recovery, assets	69		74
Commodity contracts not subject to rate recovery, assets	34		43
Investments			1
Total fair value of assets measured on a recurring basis	1,136		1,074
Interest rate instruments, liabilities	124		126
Commodity contracts subject to rate recovery, liabilities	15		9
Commodity contracts not subject to rate recovery, liabilities	10		18
Total fair value of liabilities measured on a recurring basis	149		153
San Diego Gas and Electric Company and Subsidiary [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Nuclear decommissioning trusts - equity securities	599		539
Nuclear decommissioning trusts - Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies	133		156
Nuclear decomissioning trusts - Municipal debt securities	104		63
Nuclear decommissioning trusts - Other debt securities	134		130
Nuclear decommissioning trusts - Total debt securities	371		349
Total nuclear decommissioning trusts	970	[1]	888	[1]
Commodity contracts subject to rate recovery, assets	67		73
Commodity contracts not subject to rate recovery, assets	2		1
Total fair value of assets measured on a recurring basis	1,039		962
Interest rate instruments, liabilities	59		81
Commodity contracts subject to rate recovery, liabilities	15		8
Total fair value of liabilities measured on a recurring basis	74		89
Southern California Gas Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commodity contracts subject to rate recovery, assets	2		1
Commodity contracts not subject to rate recovery, assets	3		3
Total fair value of assets measured on a recurring basis	5		4
Commodity contracts subject to rate recovery, liabilities			1
Total fair value of liabilities measured on a recurring basis			1
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Nuclear decommissioning trusts - equity securities	599		539
Nuclear decommissioning trusts - Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies	77		87
Nuclear decomissioning trusts - Municipal debt securities	0		0
Nuclear decommissioning trusts - Other debt securities	0		0
Nuclear decommissioning trusts - Total debt securities	77		87
Total nuclear decommissioning trusts	676	[1]	626	[1]
Interest rate instruments, assets	0		0
Commodity contracts subject to rate recovery, assets	12		13
Commodity contracts not subject to rate recovery, assets	22		28
Investments			1
Total fair value of assets measured on a recurring basis	710		668
Interest rate instruments, liabilities	0		0
Commodity contracts subject to rate recovery, liabilities	13		23
Commodity contracts not subject to rate recovery, liabilities	2		6
Total fair value of liabilities measured on a recurring basis	15		29
Level 1 | San Diego Gas and Electric Company and Subsidiary [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Nuclear decommissioning trusts - equity securities	599		539
Nuclear decommissioning trusts - Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies	77		87
Nuclear decomissioning trusts - Municipal debt securities	0		0
Nuclear decommissioning trusts - Other debt securities	0		0
Nuclear decommissioning trusts - Total debt securities	77		87
Total nuclear decommissioning trusts	676	[1]	626	[1]
Commodity contracts subject to rate recovery, assets	10		12
Commodity contracts not subject to rate recovery, assets	2		1
Total fair value of assets measured on a recurring basis	688		639
Interest rate instruments, liabilities	0		0
Commodity contracts subject to rate recovery, liabilities	13		23
Total fair value of liabilities measured on a recurring basis	13		23
Level 1 | Southern California Gas Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commodity contracts subject to rate recovery, assets	2		1
Commodity contracts not subject to rate recovery, assets	3		3
Total fair value of assets measured on a recurring basis	5		4
Commodity contracts subject to rate recovery, liabilities			0
Total fair value of liabilities measured on a recurring basis			0
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	56		69
Nuclear decomissioning trusts - Municipal debt securities	104		63
Nuclear decommissioning trusts - Other debt securities	134		130
Nuclear decommissioning trusts - Total debt securities	294		262
Total nuclear decommissioning trusts	294	[1]	262	[1]
Interest rate instruments, assets	63		68
Commodity contracts subject to rate recovery, assets	0		0
Commodity contracts not subject to rate recovery, assets	12		15
Investments			0
Total fair value of assets measured on a recurring basis	369		345
Interest rate instruments, liabilities	124		126
Commodity contracts subject to rate recovery, liabilities	15		9
Commodity contracts not subject to rate recovery, liabilities	15		23
Total fair value of liabilities measured on a recurring basis	154		158
Level 2 | San Diego Gas and Electric Company and Subsidiary [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	56		69
Nuclear decomissioning trusts - Municipal debt securities	104		63
Nuclear decommissioning trusts - Other debt securities	134		130
Nuclear decommissioning trusts - Total debt securities	294		262
Total nuclear decommissioning trusts	294	[1]	262	[1]
Commodity contracts subject to rate recovery, assets	0		0
Commodity contracts not subject to rate recovery, assets	0		0
Total fair value of assets measured on a recurring basis	294		262
Interest rate instruments, liabilities	59		81
Commodity contracts subject to rate recovery, liabilities	15		8
Total fair value of liabilities measured on a recurring basis	74		89
Level 2 | Southern California Gas Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commodity contracts subject to rate recovery, assets	0		0
Commodity contracts not subject to rate recovery, assets	0		0
Total fair value of assets measured on a recurring basis	0		0
Commodity contracts subject to rate recovery, liabilities			1
Total fair value of liabilities measured on a recurring basis			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	0	[1]	0	[1]
Interest rate instruments, assets	0		0
Commodity contracts subject to rate recovery, assets	57		61
Commodity contracts not subject to rate recovery, assets	0		0
Investments			0
Total fair value of assets measured on a recurring basis	57		61
Interest rate instruments, liabilities	0		0
Commodity contracts subject to rate recovery, liabilities	0		0
Commodity contracts not subject to rate recovery, liabilities	0		0
Total fair value of liabilities measured on a recurring basis	0		0
Level 3 | San Diego Gas and Electric Company and Subsidiary [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	0	[1]	0	[1]
Commodity contracts subject to rate recovery, assets	57		61
Commodity contracts not subject to rate recovery, assets	0		0
Total fair value of assets measured on a recurring basis	57		61
Interest rate instruments, liabilities	0		0
Commodity contracts subject to rate recovery, liabilities	0		0
Total fair value of liabilities measured on a recurring basis	0		0
Level 3 | Southern California Gas Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commodity contracts subject to rate recovery, assets	0		0
Commodity contracts not subject to rate recovery, assets	0		0
Total fair value of assets measured on a recurring basis	0		0
Commodity contracts subject to rate recovery, liabilities			0
Total fair value of liabilities measured on a recurring basis			0
Collateral Netted [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	0	[1]	0	[1]
Interest rate instruments, assets	0		0
Commodity contracts subject to rate recovery, assets	0		0
Commodity contracts not subject to rate recovery, assets	0		0
Investments			0
Total fair value of assets measured on a recurring basis	0		0
Interest rate instruments, liabilities	0		0
Commodity contracts subject to rate recovery, liabilities	(13)		(23)
Commodity contracts not subject to rate recovery, liabilities	(7)		(11)
Total fair value of liabilities measured on a recurring basis	(20)		(34)
Collateral Netted [Member] | San Diego Gas and Electric Company and Subsidiary [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	0	[1]	0	[1]
Commodity contracts subject to rate recovery, assets	0		0
Commodity contracts not subject to rate recovery, assets	0		0
Total fair value of assets measured on a recurring basis	0		0
Interest rate instruments, liabilities	0		0
Commodity contracts subject to rate recovery, liabilities	(13)		(23)
Total fair value of liabilities measured on a recurring basis	(13)		(23)
Collateral Netted [Member] | Southern California Gas Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commodity contracts subject to rate recovery, assets	0		0
Commodity contracts not subject to rate recovery, assets	0		0
Total fair value of assets measured on a recurring basis	0		0
Commodity contracts subject to rate recovery, liabilities			0
Total fair value of liabilities measured on a recurring basis			$ 0

[1] Excludes cash balances and cash equivalents.