SIGNIFICANT ACCOUNTING POLICIES AND OTHER FINANCIAL DATA - CHANGES IN ACCUMULATED OTHER COMPREHENSIVE INCOME (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance	$ 23,373	$ 19,929
AOCI, ending balance	25,981	23,373	$ 19,929
San Diego Gas and Electric Company [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance	7,730	7,100
AOCI, ending balance	8,249	7,730	7,100
SoCalGas
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance	5,144	4,748
AOCI, ending balance	5,442	5,144	4,748
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance	(64)	(607)	(564)
OCI before reclassifications(3)	(34)	(102)	(43)
Amounts reclassified from AOCI(3)	19	645	0
Total other comprehensive income (loss)	(15)	543	(43)
AOCI, ending balance	(79)	(64)	(607)
AOCI associated with noncontrolling interests	19
Foreign currency translation adjustments | IEnova
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI associated with noncontrolling interests	28	4
Foreign currency translation adjustments | Cumulative Effect, Period of Adoption, Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance			0
Financial instruments
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance	(331)	(215)	(82)
OCI before reclassifications(3)	62	(163)	(116)
Amounts reclassified from AOCI(3)	113	47	8
Total other comprehensive income (loss)	175	(116)	(108)
AOCI, ending balance	(156)	(331)	(215)
AOCI associated with noncontrolling interests	47
Financial instruments | IEnova
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI associated with noncontrolling interests	16	3
Financial instruments | Cumulative Effect, Period of Adoption, Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance			(25)
Financial instruments | SoCalGas
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance	(13)	(13)	(12)
OCI before reclassifications(3)	0	0	0
Amounts reclassified from AOCI(3)	0	0	1
Total other comprehensive income (loss)	0	0	1
AOCI, ending balance	(13)	(13)	(13)
Financial instruments | SoCalGas | Cumulative Effect, Period of Adoption, Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance			(2)
Pension and other postretirement benefits
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance	(105)	(117)	(118)
OCI before reclassifications(3)	8	(26)	(18)
Amounts reclassified from AOCI(3)	14	38	36
Total other comprehensive income (loss)	22	12	18
AOCI, ending balance	(83)	(105)	(117)
Pension and other postretirement benefits | San Diego Gas and Electric Company [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from AOCI(3)		3
Pension and other postretirement benefits | SoCalGas
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from AOCI(3)			4
Pension and other postretirement benefits | Cumulative Effect, Period of Adoption, Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance			(17)
Pension and other postretirement benefits | San Diego Gas and Electric Company [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance	(10)	(16)	(10)
OCI before reclassifications(3)	(1)	(4)	(5)
Amounts reclassified from AOCI(3)	1	10	1
Total other comprehensive income (loss)	0	6	(4)
AOCI, ending balance	(10)	(10)	(16)
Pension and other postretirement benefits | San Diego Gas and Electric Company [Member] | SoCalGas
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from AOCI(3)		6
Pension and other postretirement benefits | San Diego Gas and Electric Company [Member] | Cumulative Effect, Period of Adoption, Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance			(2)
Pension and other postretirement benefits | SoCalGas
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance	(18)	(10)	(8)
OCI before reclassifications(3)	(2)	(10)	(4)
Amounts reclassified from AOCI(3)	2	2	4
Total other comprehensive income (loss)	0	(8)	0
AOCI, ending balance	(18)	(18)	(10)
Pension and other postretirement benefits | SoCalGas | Cumulative Effect, Period of Adoption, Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance			(2)
Accumulated other comprehensive income (loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance	(500)	(939)	(764)
OCI before reclassifications(3)	36	(291)	(177)
Amounts reclassified from AOCI(3)	146	730	44
Total other comprehensive income (loss)	182	439	(133)
AOCI, ending balance	(318)	(500)	(939)
Accumulated other comprehensive income (loss) | Cumulative Effect, Period of Adoption, Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance			(42)
Accumulated other comprehensive income (loss) | San Diego Gas and Electric Company [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance	(10)	(16)	(10)
OCI before reclassifications(3)	(1)	(4)	(5)
Amounts reclassified from AOCI(3)	1	10	1
Total other comprehensive income (loss)	0	6	(4)
AOCI, ending balance	(10)	(10)	(16)
Accumulated other comprehensive income (loss) | San Diego Gas and Electric Company [Member] | Cumulative Effect, Period of Adoption, Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance			(2)
Accumulated other comprehensive income (loss) | SoCalGas
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance	(31)	(23)	(20)
OCI before reclassifications(3)	(2)	(10)	(4)
Amounts reclassified from AOCI(3)	2	2	5
Total other comprehensive income (loss)	0	(8)	1
AOCI, ending balance	$ (31)	$ (31)	(23)
Accumulated other comprehensive income (loss) | SoCalGas | Cumulative Effect, Period of Adoption, Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, beginning balance			$ (4)