ACQUISTION AND DIVESTITURE ACTIVITY - ASSETS HELD FOR SALE (Details) $ in Millions	1 Months Ended		9 Months Ended
	Jun. 30, 2018 USD ($)	Feb. 29, 2016 MW	Sep. 30, 2018 USD ($)	Sep. 20, 2018 USD ($)	Jun. 25, 2018 Bcf	Dec. 31, 2017 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures			$ 12,114			$ 2,527
Assets Held for Sale, Liabilities [Abstract]
Equity method investment			9,553			0	[1]
Disposal Group Held-for-sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment charges	$ 1,500
Impairment charges net of taxes and noncontrolling interests	900
Sempra Mexico [Member] | TdM [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Generating capacity | MW		625
Sempra LNG & Midstream [Member] | Disposal Group Held-for-sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment charges	1,300
Impairment charges net of taxes and noncontrolling interests	755
Sempra LNG & Midstream [Member] | Disposal Group Held-for-sale [Member] | Non-utility natural gas storage assets [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Natural gas storage capacity | Bcf					22
Impairment charges			1,300
Impairment charges net of taxes and noncontrolling interests			755
Assets Held for Sale, Assets [Abstract]
Cash and cash equivalents			0
Restricted cash			0
Accounts receivable – trade, net			4
Accounts receivable – other, net			0
Due from unconsolidated affiliates			0
Inventories			0
Fixed-price contracts and other derivatives, current			0
Other current assets			6
Property, plant and equipment, net			143
Fixed-price contracts and other derivatives, noncurrent			0
Other noncurrent assets			1
Total assets held for sale			154
Assets Held for Sale, Liabilities [Abstract]
Accounts payable – trade			0
Current portion of long-term debt			0
Fixed-price contracts and other derivatives, current			0
Other current liabilities			5
Long-term debt			0
Asset retirement obligations			8
Other noncurrent liabilities			0
Total liabilities held for sale			$ 13
Sempra Renewables [Member] | Other Jointly Wind Generation Facilities [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ownership interest			50.00%
Sempra Renewables [Member] | Disposal Group Held-for-sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment charges	200
Impairment charges net of taxes and noncontrolling interests	$ 145
Assets Held for Sale, Assets [Abstract]
Fixed-price contracts and other derivatives, current			$ 1
Fixed-price contracts and other derivatives, noncurrent			2
Assets Held for Sale, Liabilities [Abstract]
Current portion of long-term debt			7
Long-term debt			63
Sempra Renewables [Member] | Disposal Group Held-for-sale [Member] | Wind Facilities [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment charges			200
Impairment charges net of taxes and noncontrolling interests			145
Sempra Renewables [Member] | Disposal Group Held-for-sale [Member] | Solar Assets and One Wind Generation Facility [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration to be received				$ 1,540
Sempra Renewables [Member] | Disposal Group Held-for-sale [Member] | Wind and Solar Investments [Member]
Assets Held for Sale, Assets [Abstract]
Cash and cash equivalents			26
Restricted cash			4
Accounts receivable – trade, net			13
Accounts receivable – other, net			1
Due from unconsolidated affiliates			3
Inventories			5
Fixed-price contracts and other derivatives, current			1
Other current assets			4
Property, plant and equipment, net			1,664
Fixed-price contracts and other derivatives, noncurrent			2
Other noncurrent assets			4
Total assets held for sale			1,727
Assets Held for Sale, Liabilities [Abstract]
Accounts payable – trade			8
Current portion of long-term debt			7
Fixed-price contracts and other derivatives, current			2
Other current liabilities			6
Long-term debt			63
Asset retirement obligations			57
Other noncurrent liabilities			2
Total liabilities held for sale			145
Bay Gas [Member] | Sempra LNG & Midstream [Member] | Disposal Group Held-for-sale [Member] | Non-utility natural gas storage assets [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Natural gas storage capacity | Bcf					20
Ownership interest					90.90%
Operating Segments [Member] | Sempra LNG & Midstream [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures			1,252			$ 997
Operating Segments [Member] | Sempra Renewables [Member] | Wind and Solar Investments [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures			$ 600

[1] Derived from audited financial statements.