DEBT AND CREDIT FACILITIES - LONG TERM DEBT (Details) - USD ($) $ in Millions		1 Months Ended
Jan. 12, 2018	Jan. 31, 2018
Debt Instrument [Line Items]
Repayments of debt	$ 800	$ 800
Sempra Texas Holdings Corp [Member]
Debt Instrument [Line Items]
Proceeds from issuance of debt	4,900
Debt discount and debt issuance costs	68
Sempra Texas Holdings Corp [Member] \| Floating Rate Notes due 2019 [Member]
Debt Instrument [Line Items]
Debt amount offered and sold	500
Sempra Texas Holdings Corp [Member] \| Floating Rate Notes due 2021 [Member]
Debt Instrument [Line Items]
Debt amount offered and sold	700
Sempra Texas Holdings Corp [Member] \| 2.400% Senior Notes due 2020 [Member]
Debt Instrument [Line Items]
Debt amount offered and sold	$ 500
Stated rate of debt offered and sold	2.40%
Sempra Texas Holdings Corp [Member] \| 2.900% Senior Notes due 2023 [Member]
Debt Instrument [Line Items]
Debt amount offered and sold	$ 500
Stated rate of debt offered and sold	2.90%
Sempra Texas Holdings Corp [Member] \| 3.400% Senior Notes due 2028 [Member]
Debt Instrument [Line Items]
Debt amount offered and sold	$ 1,000
Stated rate of debt offered and sold	3.40%
Sempra Texas Holdings Corp [Member] \| 3.800% Senior Notes due 2038 [Member]
Debt Instrument [Line Items]
Debt amount offered and sold	$ 1,000
Stated rate of debt offered and sold	3.80%
Sempra Texas Holdings Corp [Member] \| 4.000% Senior Notes due 2048 [Member]
Debt Instrument [Line Items]
Debt amount offered and sold	$ 800
Stated rate of debt offered and sold	4.00%
Sempra Texas Holdings Corp [Member] \| LIBOR [Member] \| Floating Rate Notes due 2019 [Member]
Debt Instrument [Line Items]
Spread on variable rate	25.00%
Sempra Texas Holdings Corp [Member] \| LIBOR [Member] \| Floating Rate Notes due 2021 [Member]
Debt Instrument [Line Items]
Spread on variable rate	50.00%

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

+ Details

Name:	us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

No definition available.

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

Name:	us-gaap_RepaymentsOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_BusinessAcquisitionAxis=sre_SempraTexasHoldingsCorpMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=sre_FloatingRateNotesDueTwentyNineteenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=sre_FloatingRateNotesDueTwentyTwentyOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=sre_TwoPointFourPercentSeniorNotesDueTwentyTwentyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=sre_TwoPointNinePercentSeniorNotesDueTwentyTwentyThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=sre_ThreePointFourPercentSeniorNotesDueTwentyTwentyEightMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=sre_ThreePointEightPercentSeniorNotesDueTwentyTwentyEightMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=sre_FourPercentSeniorNotesDueTwentyFortyEightMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: