v3.8.0.1

SAN ONOFRE NUCLEAR GENERATING STATION (Details) - USD ($) $ in Millions |  | 3 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 13, 2017 | Mar. 31, 2018 | Jan. 31, 2018 | Dec. 31, 2017 | [1]
Jointly Owned Utility Plant Interests [Line Items] |  |  |  |
Settlement amount awarded | $ 118 |  |  |
Percent of arbitration expenses reduction of award | 95.00% |  |  |
Settlement amount net of arbitration expense | $ 60 |  |  |
Regulatory asset threshold to cease rate recovery |  | $ 775 |  |
Regulatory asset, current |  | 241 |  | $ 325
Regulatory asset, noncurrent |  | $ 1,597 |  | 1,517
Anticipated term of dismantlement work |  | 10 years |  |
Nuclear decommissioning trusts |  | $ 1,017 |  | 1,033
San Diego Gas and Electric Company [Member] |  |  |  |
Jointly Owned Utility Plant Interests [Line Items] |  |  |  |
Settlement amount awarded | 24 |  |  |
Settlement amount net of arbitration expense | 12 |  |  |
Arbitration expense | 12 |  |  |
Legal costs | 11 |  |  |
Litigation settlement amount allocated to ratepayers and shareholders | $ 1 |  |  |
Regulatory asset, current |  | 233 |  | 316
Regulatory asset, noncurrent |  | $ 483 |  | 451
Percent of dismantlement work expense |  | 20.00% |  |
Nuclear decommissioning trusts |  | $ 1,017 |  | $ 1,033
Authorized recovery amount, nuclear decommissioning trust funding |  | 362 | $ 60 |
San Diego Gas and Electric Company [Member] | Asset Retirement Obligation Costs [Member] |  |  |  |
Jointly Owned Utility Plant Interests [Line Items] |  |  |  |
Regulatory asset |  | 153 |  |
Regulatory asset, current |  | 42 |  |
Regulatory asset, noncurrent |  | $ 111 |  |
Jointly Owned Nuclear Power Plant [Member] | San Diego Gas and Electric Company [Member] |  |  |  |
Jointly Owned Utility Plant Interests [Line Items] |  |  |  |
Jointly owned utility plant, proportionate ownership share |  | 20.00% |  |
[1] | Derived from audited financial statements.

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- Definition Authorized Recovery Amount, Nuclear Decommissioning Trust Funding. + References No definition available. + Details
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- Definition Decommission fund to pay for the costs of decontaminating and decommissioning of facilities through collection of revenues derived from utility assessments and government appropriations. Decommission fund investment for the process whereby a power station, at the end of its economic life, is taken permanently out of service and its site made available for other purposes. In the case of a nuclear station this comprises three different states of clearance. Immediately after the final closure, radioactive material such as nuclear fuel and operational waste is removed and the buildings surrounding the reactor shield are dismantled and finally the reactor itself is dismantled. + 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 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- 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
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- Definition The proportionate share of interest (percent) in a jointly owned utility plant. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 10.C) -URI http://asc.fasb.org/extlink&oid=6500719&loc=d3e659983-123033 + Details
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- Definition Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
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