v3.8.0.1

FAIR VALUE MEASUREMENTS - FINANCIAL INSTRUMENTS (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2018 | Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Foreign currency translation | $ 4 | $ 35
Carrying amount [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term amounts due from unconsolidated affiliates | 627 | 604
Long-term amounts due to unconsolidated affiliate | 35 | 35
Total long-term debt | 22,063 | 17,138
Accumulated interest outstanding | 35 | 29
Unamortized discount (net of premium) and debt issuance costs | 206 | 143
Build-to-suit and capital lease obligations | 877 | 877
Carrying amount [Member] | Otay Mesa VIE [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt, gross | 292 | 295
Fair value [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term amounts due from unconsolidated affiliates | 647 | 624
Long-term amounts due to unconsolidated affiliate | 32 | 32
Total long-term debt | 22,500 | 18,409
Fair value [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term amounts due from unconsolidated affiliates | 0 | 0
Long-term amounts due to unconsolidated affiliate | 0 | 0
Total long-term debt | 790 | 817
Fair value [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term amounts due from unconsolidated affiliates | 606 | 528
Long-term amounts due to unconsolidated affiliate | 32 | 32
Total long-term debt | 21,254 | 17,134
Fair value [Member] | Level 3 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term amounts due from unconsolidated affiliates | 41 | 96
Long-term amounts due to unconsolidated affiliate | 0 | 0
Total long-term debt | 456 | 458
San Diego Gas and Electric Company [Member] | Carrying amount [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total long-term debt | 4,848 | 4,868
Unamortized discount (net of premium) and debt issuance costs | 45 | 45
Capital lease obligations | 730 | 732
San Diego Gas and Electric Company [Member] | Fair value [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total long-term debt | 5,184 | 5,368
San Diego Gas and Electric Company [Member] | Fair value [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total long-term debt | 0 | 0
San Diego Gas and Electric Company [Member] | Fair value [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total long-term debt | 4,892 | 5,073
San Diego Gas and Electric Company [Member] | Fair value [Member] | Level 3 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total long-term debt | 292 | 295
Southern California Gas Company [Member] | Carrying amount [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total long-term debt | 3,009 | 3,009
Unamortized discount (net of premium) and debt issuance costs | 24 | 24
Capital lease obligations | 4 | 1
Southern California Gas Company [Member] | Fair value [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total long-term debt | 3,102 | 3,192
Southern California Gas Company [Member] | Fair value [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total long-term debt | 0 | 0
Southern California Gas Company [Member] | Fair value [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total long-term debt | 3,102 | 3,192
Southern California Gas Company [Member] | Fair value [Member] | Level 3 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total long-term debt | $ 0 | $ 0

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- Definition Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84164817&loc=d3e45280-112737 Reference 2: 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)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + 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)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Amount before tax of foreign currency transaction realized and unrealized gain recognized in the income statement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=64836518&loc=d3e30690-110894 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6450222&loc=d3e30840-110895 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64836518&loc=d3e30700-110894 + Details
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