v3.8.0.1

GENERAL INFORMATION AND OTHER FINANCIAL DATA - PENSION AND OTHER POSTRETIREMENT BENEFITS (Details) - USD ($) $ in Millions |  | 3 Months Ended
--- | --- | ---
Mar. 09, 2018 | Mar. 31, 2018 | Mar. 31, 2017
Pension benefits [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Reduction in plan assets due to settlement |  | $ 83 |
Service cost |  | 33 | $ 28
Interest cost |  | 35 | 37
Expected return on assets |  | (42) | (40)
Prior service cost (credit) |  | 3 | 3
Actuarial loss (gain) |  | 9 | 8
Settlements |  | 14 | 0
Net periodic benefit cost (credit) |  | 52 | 36
Regulatory adjustment |  | (45) | (12)
Total expense recognized |  | 7 | 24
Contributions by employer |  | 10 |
Expected contributions in current fiscal year |  | 226 |
Pension benefits [Member] | San Diego Gas and Electric Company [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Service cost |  | 8 | 8
Interest cost |  | 9 | 9
Expected return on assets |  | (13) | (11)
Prior service cost (credit) |  | 0 | 0
Actuarial loss (gain) |  | 1 | 2
Settlements |  | 14 | 0
Net periodic benefit cost (credit) |  | 19 | 8
Regulatory adjustment |  | (19) | (7)
Total expense recognized |  | 0 | 1
Contributions by employer |  | 2 |
Expected contributions in current fiscal year |  | 48 |
Pension benefits [Member] | Southern California Gas Company [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Service cost |  | 22 | 18
Interest cost |  | 23 | 24
Expected return on assets |  | (26) | (26)
Prior service cost (credit) |  | 2 | 2
Actuarial loss (gain) |  | 6 | 4
Net periodic benefit cost (credit) |  | 27 | 22
Regulatory adjustment |  | (26) | (5)
Total expense recognized |  | 1 | 17
Contributions by employer |  | 0 |
Expected contributions in current fiscal year |  | 113 |
Other postretirement benefits [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Service cost |  | 6 | 6
Interest cost |  | 9 | 9
Expected return on assets |  | (18) | (16)
Prior service cost (credit) |  | 0 | 0
Actuarial loss (gain) |  | (1) | (1)
Settlements |  | 0 | 0
Net periodic benefit cost (credit) |  | (4) | (2)
Regulatory adjustment |  | 4 | 2
Total expense recognized |  | 0 | 0
Contributions by employer |  | 1 |
Expected contributions in current fiscal year |  | 9 |
Other postretirement benefits [Member] | San Diego Gas and Electric Company [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Service cost |  | 1 | 1
Interest cost |  | 2 | 2
Expected return on assets |  | (3) | (3)
Prior service cost (credit) |  | 1 | 1
Actuarial loss (gain) |  | (1) | 0
Settlements |  | 0 | 0
Net periodic benefit cost (credit) |  | 0 | 1
Regulatory adjustment |  | 0 | (1)
Total expense recognized |  | 0 | 0
Contributions by employer |  | 0 |
Expected contributions in current fiscal year |  | 3 |
Other postretirement benefits [Member] | Southern California Gas Company [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Service cost |  | 4 | 4
Interest cost |  | 7 | 7
Expected return on assets |  | (14) | (13)
Prior service cost (credit) |  | (1) | (1)
Actuarial loss (gain) |  | 0 | 0
Net periodic benefit cost (credit) |  | (4) | (3)
Regulatory adjustment |  | 4 | 3
Total expense recognized |  | 0 | $ 0
Contributions by employer |  | 1 |
Expected contributions in current fiscal year |  | $ 2 |
Oncor Holdings [Member] | Sempra Texas Holdings Corp [Member] | Sempra Texas Intermediate Holding Company LLC [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Increase in liability due to acquisition | $ 21 |  |

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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(4) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(5) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(ii) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2709-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(iv)(01) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(3) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(ii) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(iv)(01) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(8) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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