v3.6.0.2

SAN ONOFRE NUCLEAR GENERATING STATION (SONGS) - NARRATIVE (Details) - USD ($) $ in Millions | 1 Months Ended | 3 Months Ended | 12 Months Ended | 48 Months Ended
--- | --- | --- | --- | ---
Dec. 31, 2016 | Apr. 30, 2016 | Oct. 31, 2015 | Dec. 31, 2015 | Mar. 31, 2015 | Dec. 31, 2016 | Dec. 31, 2014 | Dec. 31, 2016
Jointly Owned Utility Plant Interests [Line Items] |  |  |  |  |  |  |  |
Nuclear plant closure regulatory asset, noncurrent | $ 3,414 |  |  | $ 3,273 |  | $ 3,414 |  | $ 3,414
Nuclear decommissioning trusts | 1,026 |  |  | 1,063 |  | 1,026 |  | 1,026
San Onofre Nuclear Generating Station (SONGS) [Member] |  |  |  |  |  |  |  |
Jointly Owned Utility Plant Interests [Line Items] |  |  |  |  |  |  |  |
Insurance recovery |  |  | $ 400 |  |  |  |  |
Current authorized annual recovery amount from nuclear decommissioning trust funding |  | $ 4,400 |  |  |  |  |  |
San Diego Gas and Electric Company [Member] |  |  |  |  |  |  |  |
Jointly Owned Utility Plant Interests [Line Items] |  |  |  |  |  |  |  |
Nuclear plant closure regulatory asset, current | 81 |  |  | 107 |  | 81 |  | 81
Nuclear plant closure regulatory asset, noncurrent | 998 |  |  | 977 |  | 998 |  | 998
Nuclear decommissioning trusts | 1,026 |  |  | 1,063 |  | 1,026 |  | 1,026
Requested withdrawal from nuclear decommissioning trust funds | 84 |  |  |  |  |  |  |
Decommissioning liability | 637 |  |  |  |  | 637 |  | 637
Cost study estimate decommissioning escalated | $ 989 |  |  |  |  | 989 |  | $ 989
San Diego Gas and Electric Company [Member] | Year 2013 through 2016 forecasted [Member] |  |  |  |  |  |  |  |
Jointly Owned Utility Plant Interests [Line Items] |  |  |  |  |  |  |  |
Current authorized annual recovery amount from nuclear decommissioning trust funding |  |  |  |  |  | 218 |  |
Amount pending regulatory clarification |  |  |  |  |  | $ 37 |  |
San Diego Gas and Electric Company [Member] | San Onofre Nuclear Generating Station (SONGS) [Member] |  |  |  |  |  |  |  |
Jointly Owned Utility Plant Interests [Line Items] |  |  |  |  |  |  |  |
Ownership percentage | 20.00% |  |  |  |  | 20.00% |  | 20.00%
Portion of weighted average return on preferred stock included in nuclear plant return on ratebase | 50.00% |  |  |  |  | 50.00% |  | 50.00%
Return on ratebase |  |  |  |  |  |  |  | 2.35%
Loss from plant closure, after tax (cumulative) |  |  |  |  |  |  |  | $ 125
Plant closure (adjustment) loss, after tax |  |  |  | $ 2 | $ 13 |  | $ 21 |
Plant closure (adjustment) loss after settlement, after tax |  |  |  |  |  |  | $ 12 |
Insurance recovery |  |  | $ 80 |  |  |  |  |
Recovery allocation percentage |  |  | 5.00% |  |  |  |  |
Current authorized annual recovery amount from nuclear decommissioning trust funding |  | $ 899 |  |  |  |  |  |
San Diego Gas and Electric Company [Member] | San Onofre Nuclear Generating Station (SONGS) [Member] | Nuclear Plant Closure [Member] |  |  |  |  |  |  |  |
Jointly Owned Utility Plant Interests [Line Items] |  |  |  |  |  |  |  |
Nuclear plant closure regulatory asset | $ 183 |  |  |  |  | $ 183 |  | 183
Nuclear plant closure regulatory asset, current | 31 |  |  |  |  | 31 |  | 31
Nuclear plant closure regulatory asset, noncurrent | $ 152 |  |  |  |  | $ 152 |  | $ 152
Ratepayers [Member] | San Onofre Nuclear Generating Station (SONGS) [Member] |  |  |  |  |  |  |  |
Jointly Owned Utility Plant Interests [Line Items] |  |  |  |  |  |  |  |
Amount funded to customers through Energy Resource Recovery Account |  |  | $ 75 |  |  |  |  |

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- Definition Total Estimated Nuclear Decommissioning Costs, Latest Cost Study Escalated. + 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 The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.3) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 + 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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 10 -Section C + Details
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- Definition The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period. + 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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- 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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