COMMITMENTS AND CONTINGENCIES - CONTRACTUAL COMMITMENTS (Details) $ in Millions	6 Months Ended
Jun. 30, 2018 USD ($)
Sempra LNG & Midstream [Member] \| Liquefied Natural Gas Contracts [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Increase (decrease) in commitment amount, 2018	$ (206)
Increase (decrease) in commitment amount, 2019	(34)
Increase (decrease) in commitment amount, 2020	(54)
Increase (decrease) in commitment amount, 2021	(63)
Increase (decrease) in commitment amount, 2022	(59)
Increase (decrease) in commitment amount, thereafter	(284)
Operating Lease [Member] \| Sempra LNG & Midstream [Member] \| Natural Gas Contracts [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Increase (decrease) in commitment amount	(91)
Increase (decrease) in commitment amount, 2018	(104)
Increase (decrease) in commitment amount, 2019	8
Increase (decrease) in commitment amount, 2020	3
Increase (decrease) in commitment amount, 2021	2
Liquid Fuels Terminals and Renewables Projects [Member] \| Sempra Mexico [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Increase (decrease) in commitment amount	148
Increase (decrease) in commitment amount, 2018	114
Increase (decrease) in commitment amount, 2019	32
Increase (decrease) in commitment amount, thereafter	$ 2

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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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

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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