COMMITMENTS AND CONTINGENCIES - LEASES THAT HAVE NOT YET COMMENCED (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
Lessee, Lease, Description [Line Items]
Lease not yet commenced, aggregate maximum lease limit	$ 174
San Diego Gas and Electric Company [Member]
Lessee, Lease, Description [Line Items]
Lease not yet commenced, aggregate maximum lease limit, amount utilized	54
Southern California Gas Company [Member]
Lessee, Lease, Description [Line Items]
Lease not yet commenced, aggregate maximum lease limit, amount utilized	72
Sempra LNG [Member]
Lessee, Lease, Description [Line Items]
Lease not yet commenced, due in 2021	1
Lease not yet commenced, due 2022 through 2024	2
Lease not yet commenced, due after year 2024	$ 16

Lessee, Finance Lease, Lease Not yet Commenced, Aggregate Maximum Lease Limit

No definition available.

Name:	sre_LesseeFinanceLeaseLeaseNotyetCommencedAggregateMaximumLeaseLimit
Namespace Prefix:	sre_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Lessee, Finance Lease, Lease Not yet Commenced, Aggregate Maximum Lease Limit, Utilized

+ References

No definition available.

+ Details

Name:	sre_LesseeFinanceLeaseLeaseNotyetCommencedAggregateMaximumLeaseLimitUtilized
Namespace Prefix:	sre_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Lessee, Operating Lease, Lease Not Yet Commenced, Payments, After Year Four

+ References

No definition available.

+ Details

Name:	sre_LesseeOperatingLeaseLeaseNotYetCommencedPaymentsAfterYearFour
Namespace Prefix:	sre_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Lessee, Operating Lease, Lease Not Yet Commenced, Payments, Year One

+ References

No definition available.

+ Details

Name:	sre_LesseeOperatingLeaseLeaseNotYetCommencedPaymentsYearOne
Namespace Prefix:	sre_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Lessee, Operating Lease, Lease Not Yet Commenced, Payments, Year Two Through Four

+ References

No definition available.

+ Details

Name:	sre_LesseeOperatingLeaseLeaseNotYetCommencedPaymentsYearTwoThroughFour
Namespace Prefix:	sre_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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

- Details

Name:	dei_LegalEntityAxis=sre_SanDiegoGasAndElectricCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=sre_SouthernCaliforniaGasCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=sre_SempraLNGMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: