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Environmental Costs, Potential Monetary Sanctions, Threshold, Actual Amount

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Payments For Accrued Environmental Loss Contingencies, After Year Five

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Payments For Accrued Environmental Loss Contingencies, Next Twelve Month

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Payments For Accrued Environmental Loss Contingencies, Year Five

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Payments For Accrued Environmental Loss Contingencies, Year Four

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Payments For Accrued Environmental Loss Contingencies, Year Three

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Payments For Accrued Environmental Loss Contingencies, Year Two

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Site contingency, sites completed.

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Site contingency, sites in process.

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Amount of imputed interest necessary to reduce (reconcile) the undiscounted amount of the accrual for environmental loss contingencies to the present value.

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Rate applied to the undiscounted amount of environmental loss contingencies to arrive at the present value recorded as of the balance sheet date.

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Undiscounted amount of the accrual for environmental loss contingencies.

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Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

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Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable after twelve months or beyond the next operating cycle if longer.

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Amount of environmental remediation costs capitalized. These expenditures may relate to long-lived improvements in operating facilities.

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Total anticipated costs associated with remediation, site restoration, postclosure, monitoring commitments, or other exit costs that may occur on the sale, disposal, or abandonment of a particular property resulting from unanticipated contamination of the assets.

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Best estimate of the loss exposure for reasonably possible environmental contingencies at an individual site for which no accrual has been recorded.

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COMMITMENTS AND CONTINGENCIES - ENVIRONMENTAL ISSUES (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) site	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Environmental Issues [Line Items]
Capital expendistures for environmental issues	$ 76	$ 80	$ 100
Accrued liability for environmental matters, discount	$ 9
Accrued liability for environmental matters, discount rate (as a percent)	1.50%
Accrual for environmental loss contingencies	$ 60
Expected future payments for accruals, 2021	12
Expected future payments for accruals, 2022	16
Expected future payments for accruals, 2023	3
Expected future payments for accruals, 2024	6
Expected future payments for accruals, 2025	3
Expected future payments for accruals, thereafter	58
Minimum [Member]
Environmental Issues [Line Items]
Potential monetary sanctions threshold	1
Sempra Energy [Member]
Environmental Issues [Line Items]
Accrual for environmental loss contingencies, current	11
Accrual for environmental loss contingencies, noncurrent	49
Potential monetary sanctions threshold, actual amount	45
San Diego Gas and Electric Company [Member]
Environmental Issues [Line Items]
Capital expendistures for environmental issues	39	39	38
Accrual for environmental loss contingencies	19
Accrual for environmental loss contingencies, current	1
Accrual for environmental loss contingencies, noncurrent	18
Potential monetary sanctions threshold, actual amount	16
Southern California Gas Company [Member]
Environmental Issues [Line Items]
Capital expendistures for environmental issues	37	$ 41	$ 62
Accrual for environmental loss contingencies	40
Accrual for environmental loss contingencies, current	10
Accrual for environmental loss contingencies, noncurrent	30
Potential monetary sanctions threshold, actual amount	15
Other Sempra Energy [Member]
Environmental Issues [Line Items]
Accrual for environmental loss contingencies	1
Manufactured Gas Sites [Member]
Environmental Issues [Line Items]
Accrual for environmental loss contingencies	$ 36
Manufactured Gas Sites [Member] \| San Diego Gas and Electric Company [Member]
Environmental Issues [Line Items]
Number of sites complete \| site	3
Number of sites in process \| site	0
Accrual for environmental loss contingencies	$ 0
Manufactured Gas Sites [Member] \| Southern California Gas Company [Member]
Environmental Issues [Line Items]
Number of sites complete \| site	39
Number of sites in process \| site	3
Accrual for environmental loss contingencies	$ 36
Manufactured Gas Sites [Member] \| Other Sempra Energy [Member]
Environmental Issues [Line Items]
Accrual for environmental loss contingencies	0
Waste Disposal Sites [Member]
Environmental Issues [Line Items]
Accrual for environmental loss contingencies	$ 10
Waste Disposal Sites [Member] \| San Diego Gas and Electric Company [Member]
Environmental Issues [Line Items]
Number of sites complete \| site	2
Number of sites in process \| site	1
Accrual for environmental loss contingencies	$ 6
Waste Disposal Sites [Member] \| Southern California Gas Company [Member]
Environmental Issues [Line Items]
Number of sites complete \| site	5
Number of sites in process \| site	2
Accrual for environmental loss contingencies	$ 3
Waste Disposal Sites [Member] \| Other Sempra Energy [Member]
Environmental Issues [Line Items]
Accrual for environmental loss contingencies	1
Other Hazardous Waste Sites [Member]
Environmental Issues [Line Items]
Accrual for environmental loss contingencies	14
Other Hazardous Waste Sites [Member] \| San Diego Gas and Electric Company [Member]
Environmental Issues [Line Items]
Accrual for environmental loss contingencies	13
Other Hazardous Waste Sites [Member] \| Southern California Gas Company [Member]
Environmental Issues [Line Items]
Accrual for environmental loss contingencies	1
Other Hazardous Waste Sites [Member] \| Other Sempra Energy [Member]
Environmental Issues [Line Items]
Accrual for environmental loss contingencies	0
SONGS Sites [Member] \| San Diego Gas and Electric Company [Member]
Environmental Issues [Line Items]
Estimated SONGS mitigation costs, recoverable in rates	84
SONGS mitigation costs incurred	47
SONGS mitigation costs remaining	$ 37