DEBT AND CREDIT FACILITIES - LINES OF CREDIT (Details)		1 Months Ended	3 Months Ended
	Apr. 01, 2020 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2020 USD ($) lender
Line of Credit Facility [Line Items]
Standby letters of credit outstanding		$ 615,000,000	$ 615,000,000
Sempra Energy [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity		1,250,000,000	1,250,000,000
Line of Credit Facility, Current Borrowing Capacity		(1,250,000,000)	(1,250,000,000)
Available unused credit		0	0
Capacity for issuance of letters of credit		200,000,000	200,000,000
Option to request		500,000,000	500,000,000
Sempra Global [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity		3,185,000,000	3,185,000,000
Line of Credit Facility, Current Borrowing Capacity		0	0
Available unused credit		1,960,000,000	1,960,000,000
San Diego Gas and Electric Company [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity		1,500,000,000	1,500,000,000
Line of Credit Facility, Current Borrowing Capacity		(200,000,000)	(200,000,000)
Available unused credit		$ 1,300,000,000	$ 1,300,000,000
Maximum ratio of indebtedness to total capitalization		65.00%	65.00%
Southern California Gas Company [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 750,000,000	$ 750,000,000
Line of Credit Facility, Current Borrowing Capacity		0	0
Available unused credit		750,000,000	750,000,000
Capacity for issuance of letters of credit		100,000,000	100,000,000
Option to request		$ 250,000,000	$ 250,000,000
Maximum ratio of indebtedness to total capitalization		65.00%	65.00%
Sempra U.S. Businesses [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 6,685,000,000	$ 6,685,000,000
Line of Credit Facility, Current Borrowing Capacity		(1,450,000,000)	(1,450,000,000)
Available unused credit		$ 4,010,000,000	$ 4,010,000,000
Maximum ratio of indebtedness to total capitalization		65.00%	65.00%
Foreign Line of Credit [Member] | Sempra Mexico [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 1,880,000,000	$ 1,880,000,000
Amount outstanding		(1,744,000,000)	(1,744,000,000)
Available unused credit		136,000,000	136,000,000
Commercial Paper [Member] | Sempra Energy [Member]
Line of Credit Facility [Line Items]
Amount outstanding		0	0
Commercial Paper [Member] | Sempra Global [Member]
Line of Credit Facility [Line Items]
Amount outstanding		(1,225,000,000)	(1,225,000,000)
Unamortized debt discount		1,000,000	1,000,000
Commercial Paper [Member] | San Diego Gas and Electric Company [Member]
Line of Credit Facility [Line Items]
Amount outstanding		0	0
Commercial Paper [Member] | Southern California Gas Company [Member]
Line of Credit Facility [Line Items]
Amount outstanding		0	0
Commercial Paper [Member] | Sempra U.S. Businesses [Member]
Line of Credit Facility [Line Items]
Amount outstanding		(1,225,000,000)	(1,225,000,000)
Foreign Committed Lines of Credit, Due February 2024 [Member] | Foreign Line of Credit [Member] | Sempra Mexico [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity		1,500,000,000	1,500,000,000
Amount outstanding		(1,364,000,000)	(1,364,000,000)
Available unused credit		136,000,000	$ 136,000,000
Term of debt instrument			5 years
Number of lenders | lender			10
Foreign Committed Lines of Credit, Due April 2022 [Member] | Foreign Line of Credit [Member] | Sempra Mexico [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity		100,000,000	$ 100,000,000
Amount outstanding		(100,000,000)	(100,000,000)
Available unused credit		0	$ 0
Term of debt instrument			3 years
Foreign Committed Lines of Credit, Due September 2021 [Member] | Foreign Line of Credit [Member] | Sempra Mexico [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity		280,000,000	$ 280,000,000
Amount outstanding		(280,000,000)	(280,000,000)
Available unused credit		0	$ 0
Term of debt instrument			2 years
Term Loan [Member] | Sempra Energy [Member]
Line of Credit Facility [Line Items]
Net proceeds of debt		1,524,000,000
Debt issuance costs		1,000,000	$ 1,000,000
Debt Instrument, Basis Spread on Variable Rate			1.72%
Term Loan [Member] | San Diego Gas and Electric Company [Member]
Line of Credit Facility [Line Items]
Net proceeds of debt		$ 200,000,000
Debt Instrument, Basis Spread on Variable Rate			1.73%
Subsequent Event [Member] | Term Loan [Member] | Sempra Energy [Member]
Line of Credit Facility [Line Items]
Net proceeds of debt	$ 75,000,000