EMPLOYEE BENEFIT PLANS - NARRATIVE (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Dedicated assets in support of certain benefit plans	$ 512,000	$ 488,000
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan amendments	0	5,000
Settlement charges	22,000	28,000	$ 12,000
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan amendments	0	0
Settlement charges	0	0	0
Increase in liability due to special termination benefits			5,000
San Diego Gas and Electric Company [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan amendments	0	3,000
Settlement charges	0	0	4,000
San Diego Gas and Electric Company [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan amendments	0	0
Settlement charges	0	0	0
Increase in liability due to special termination benefits			3,000
Southern California Gas Company [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan amendments	0	2,000
Southern California Gas Company [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan amendments	0	0
Increase in liability due to special termination benefits			2,000
Nonqualified Plan [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation payment for settlement	22,000	24,000	12,000
Nonqualified Plan [Member] | San Diego Gas and Electric Company [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation payment for settlement			4,000
Qualified Plan [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation payment for settlement			54,000
Qualified Plan [Member] | San Diego Gas and Electric Company [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation payment for settlement			22,000
Qualified Plan [Member] | Southern California Gas Company [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation payment for settlement			32,000
Oncor Electric Delivery Company LLC [Member] | Sempra Texas Intermediate Holding Company LLC [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Gain (loss) arising during the period	$ 11,000	$ 27,000	27,000
Voluntary Retirement Enhancement Program [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Settlement charges			$ 100,000