COMMITMENTS AND CONTINGENCIES - CONTRACTUAL COMMITMENTS (Details) - USD ($) $ in Millions		3 Months Ended
Mar. 13, 2017	Mar. 31, 2018
Unrecorded Unconditional Purchase Obligation [Line Items]
Settlement amount received	$ 118
Sempra LNG & Midstream [Member] \| Liquefied Natural Gas Contracts [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Increase (decrease) in commitment amount, 2018		$ (112)
Increase (decrease) in commitment amount, 2019		(55)
Increase (decrease) in commitment amount, 2020		(42)
Increase (decrease) in commitment amount, 2021		(40)
Increase (decrease) in commitment amount, 2022		(30)
Increase (decrease) in commitment amount, thereafter		(110)
San Diego Gas and Electric Company [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Settlement amount received	$ 24
Operating Lease [Member] \| Sempra LNG & Midstream [Member] \| Natural Gas Contracts [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Increase (decrease) in commitment amount		(54)
Increase (decrease) in commitment amount, 2018		(62)
Increase (decrease) in commitment amount, 2019		3
Increase (decrease) in commitment amount, 2020		2
Increase (decrease) in commitment amount, 2021		2
Increase (decrease) in commitment amount, 2022		1
Renewables Projects \| Sempra Mexico [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Increase (decrease) in commitment amount		81
Increase (decrease) in commitment amount, 2018		53
Increase (decrease) in commitment amount, 2019		28
Liquid Fuels Terminals \| Sempra Mexico [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Increase (decrease) in commitment amount		94
Increase (decrease) in commitment amount, 2018		91
Increase (decrease) in commitment amount, 2019		2
Increase (decrease) in commitment amount, thereafter		$ 1

Increase (Decrease) in Unrecorded Unconditional Purchase Obligation

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- Definition

Increase (Decrease) in Unrecorded Unconditional Purchase Obligation, After Five Years

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- Definition

Increase (Decrease) in Unrecorded Unconditional Purchase Obligation, Remainder of Fiscal Year

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- Definition

Increase (Decrease) in Unrecorded Unconditional Purchase Obligation, Year Five

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Increase (Decrease) in Unrecorded Unconditional Purchase Obligation, Year Four

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- Definition

Increase (Decrease) in Unrecorded Unconditional Purchase Obligation, Year Three

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Increase (Decrease) in Unrecorded Unconditional Purchase Obligation, Year Two

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- Definition

Amount awarded from other party in judgment or settlement of litigation.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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