SIGNIFICANT ACCOUNTING POLICIES AND OTHER FINANCIAL DATA - VARIABLE INTEREST ENTITIES (Details) $ in Millions		9 Months Ended
	Mar. 09, 2018	Oct. 03, 2019 USD ($) MW	Dec. 31, 2019 USD ($)	Aug. 23, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
ASSETS
Cash and cash equivalents			$ 108		$ 102
Inventories			277		258
Total current assets			3,339		3,645
Property, plant and equipment, net			36,452		34,439
Other long-term assets			732		962
Total assets			65,665		60,638	$ 50,454
Liabilities [Abstract]
Other current liabilities			866		935
Total current liabilities			9,150		7,523
Asset retirement obligations			3,083		2,972	2,876
Deferred credits and other			2,048		1,493
Equity [Abstract]
Other noncontrolling interests			1,856		2,090
Total liabilities and equity			65,665		60,638
Equity method investment			11,519		9,652
San Diego Gas and Electric Company [Member]
ASSETS
Cash and cash equivalents			10		8
Inventories			94		102
Total current assets			1,158		894
Property, plant and equipment, net			16,967		16,310
Other long-term assets			202		420
Total assets			20,560		19,225
Liabilities [Abstract]
Other current liabilities			176		141
Total current liabilities			1,310		1,428
Asset retirement obligations			866		874	$ 839
Deferred credits and other			677		488
Equity [Abstract]
Other noncontrolling interests			0		100
Total liabilities and equity			20,560		19,225
San Diego Gas and Electric Company [Member] | Otay Mesa VIE [Member]
Investments [Abstract]
Generating capacity (in mw) | MW		605
Put option		$ 280
Equity of Variable interest entity					100
Sempra Mexico [Member]
Equity [Abstract]
VIE, carrying amount of assets			126		286
Sempra Renewables [Member] | Noncontrolling Tax Equity Investors [Member]
Equity [Abstract]
Assets held for sale					301
VIE, liabilities held-for-sale					9
VIE, equity amount					158
Sempra LNG [Member] | Cameron LNG Holdings [Member]
Equity [Abstract]
Equity method investment			1,256		1,271
Oncor Electric Delivery Holdings Company LLC [Member] | Sempra Texas Utilities [Member]
Equity [Abstract]
Equity method investment			$ 11,519		$ 9,652
Oncor Electric Delivery Company LLC [Member]
Equity [Abstract]
Acquired percentage interest	80.25%
Sempra Texas Holdings Corp [Member] | Oncor Electric Delivery Holdings Company LLC [Member] | Sempra Texas Intermediate Holding Company LLC [Member]
Equity [Abstract]
Ownership percentage in consolidated entity	100.00%
Sempra Texas Holdings Corp [Member] | Oncor Electric Delivery Company LLC [Member]
Equity [Abstract]
Acquired percentage interest	80.03%
Otay Mesa VIE [Member] | Variable Interest Entity, Not Primary Beneficiary [Member]
ASSETS
Cash and cash equivalents				$ 8
Accounts receivable, net				11
Inventories				4
Total current assets				23
Property, plant and equipment, net				272
Other long-term assets				27
Total assets				322
Liabilities [Abstract]
Accounts payable				10
Other current liabilities				2
Total current liabilities				12
Asset retirement obligations				2
Deferred credits and other				27
Total deferred credits and other liabilities				29
Equity [Abstract]
Other noncontrolling interests				281
Total liabilities and equity				$ 322