GENERAL INFORMATION AND OTHER FINANCIAL DATA - VARIABLE INTEREST ENTITIES (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Variable Interest Entities [Line Items]
Property, plant and equipment	$ 38,784	$ 36,452	[1]
Finance lease obligations	1,335	1,289
Equity method investment	11,962	11,519	[1]
Assets	67,222	65,665	[1]
Sempra Texas Utilities [Member] | Oncor Holdings [Member]
Variable Interest Entities [Line Items]
Equity method investment	11,962	11,519
Sempra LNG [Member]
Variable Interest Entities [Line Items]
Maximum exposure under guarantor obligations	4,000
Sempra LNG [Member] | Cameron LNG Holdings [Member]
Variable Interest Entities [Line Items]
Equity method investment	433	1,256
San Diego Gas and Electric Company [Member]
Variable Interest Entities [Line Items]
Property, plant and equipment	17,923	16,967	[1]
Finance lease obligations	1,278	1,270
Assets	$ 22,421	20,560	[1]
Oncor Electric Delivery Company LLC. [Member] | Oncor Holdings [Member] | Sempra Texas Utilities [Member]
Variable Interest Entities [Line Items]
Ownership interest (as a percent)	80.25%
Sempra Texas Holdings Corp [Member] | Oncor Holdings [Member] | Sempra Texas Intermediate Holding Company LLC [Member]
Variable Interest Entities [Line Items]
Ownership percentage in consolidated entity	100.00%
Variable Interest Entity, Not Primary Beneficiary [Member] | Sempra LNG [Member]
Variable Interest Entities [Line Items]
Maximum exposure under guarantor obligations	$ 979
Variable Interest Entity, Not Primary Beneficiary [Member] | San Diego Gas and Electric Company [Member]
Variable Interest Entities [Line Items]
Property, plant and equipment	1,242	1,255
Finance lease obligations	$ 1,242	1,255
Variable Interest Entity, Primary Beneficiary [Member] | Sempra Mexico [Member]
Variable Interest Entities [Line Items]
Assets		$ 126

[1] Derived from audited financial statements.