v3.8.0.1

SAN ONOFRE NUCLEAR GENERATING STATION - NUCLEAR FUEL DISPOSAL (Details) - San Diego Gas and Electric Company [Member] - USD ($) $ in Millions |  | 1 Months Ended
--- | --- | ---
Apr. 18, 2016 | Apr. 30, 2018 | Mar. 31, 2018 | Oct. 31, 2017 | May 31, 2017 | Feb. 28, 2017 | Sep. 30, 2016 | May 31, 2016
Total Ownership [Member] |  |  |  |  |  |  |  |
Jointly Owned Utility Plant Interests [Line Items] |  |  |  |  |  |  |  |
Spent nuclear fuel damages awarded | $ 162 |  | $ 44 |  |  | $ 43 |  |
Filed claims amount |  |  |  | $ 58 |  |  | $ 56 |
SDG&E Ownership [Member] |  |  |  |  |  |  |  |
Jointly Owned Utility Plant Interests [Line Items] |  |  |  |  |  |  |  |
Spent nuclear fuel damages awarded |  |  | $ 9 |  | $ 9 |  |  | $ 32
Decrease In SONGS regulatory asset |  |  |  |  |  |  |  | 23
Decrease In nuclear decommissioning balancing account |  |  |  |  |  |  |  | 8
Decrease In operation and maintenance cost balancing account |  |  |  |  |  |  |  | $ 1
Filed claims amount |  |  |  | $ 12 |  |  |  |
Subsequent Event [Member] | Total Ownership [Member] |  |  |  |  |  |  |  |
Jointly Owned Utility Plant Interests [Line Items] |  |  |  |  |  |  |  |
Filed claims amount |  | $ 1 |  |  |  |  |  |

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- Definition The increase (decrease) during the reporting period in the asset created by the regulatory convention in which costs and revenues associated with certain utility expenses (such as fuel) are accumulated but on which no return is earned. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 + Details
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