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Commitments and Contingencies - Palo Verde Nuclear Generating Station and Contractual Obligations (Details) |  |  | 9 Months Ended |
--- | --- | --- | --- | ---
Oct. 31, 2016 USD ($) | Aug. 18, 2014 USD ($) | Sep. 30, 2016 USD ($) time_period power_plant claim | Dec. 31, 1986 Trust
Breach of Contract for Disposal of Spent Nuclear Fuel and/or High Level Radioactive Waste |  |  |  |
Commitments and Contingencies |  |  |  |
Litigation settlement amount |  | $ 57,400,000 |  |
Proceeds from legal settlements |  |  | $ 53,900,000 |
Arizona Public Service Company |  |  |  |
Commitments and Contingencies |  |  |  |
Maximum insurance against public liability per occurrence for a nuclear incident (up to) |  |  | 13,400,000,000 |
Maximum available nuclear liability insurance (up to) |  |  | 375,000,000 |
Remaining nuclear liability insurance through mandatory industry wide retrospective assessment program |  |  | 13,000,000,000 |
Maximum retrospective premium assessment per reactor for each nuclear liability incident |  |  | 127,300,000 |
Annual limit per incident with respect to maximum retrospective premium assessment |  |  | $ 18,900,000 |
Number of VIE lessor trusts |  |  | 3 | 3
Maximum potential retrospective assessment per incident of APS |  |  | $ 111,100,000 |
Annual payment limitation with respect to maximum potential retrospective premium assessment |  |  | 16,600,000 |
Amount of "all risk" (including nuclear hazards) insurance for property damage to, and decontamination of, property at Palo Verde |  |  | 2,800,000,000 |
Maximum amount that APS could incur under the current NEIL policies for each retrospective assessment |  |  | 23,800,000 |
Collateral assurance provided based on rating triggers |  |  | $ 64,000,000 |
Period to provide collateral assurance based on rating triggers |  |  | 20 days |
Arizona Public Service Company | Breach of Contract for Disposal of Spent Nuclear Fuel and/or High Level Radioactive Waste |  |  |  |
Commitments and Contingencies |  |  |  |
Litigation settlement amount |  | $ 16,700,000 |  |
Number of claims submitted | claim |  |  | 2 |
Number of settlement agreement time periods | time_period |  |  | 2 |
Proceeds from legal settlements |  |  | $ 15,700,000 |
Subsequent Event | Breach of Contract for Disposal of Spent Nuclear Fuel and/or High Level Radioactive Waste |  |  |  |
Commitments and Contingencies |  |  |  |
Litigation settlement amount | $ 11,300,000 |  |  |
Subsequent Event | Arizona Public Service Company | Breach of Contract for Disposal of Spent Nuclear Fuel and/or High Level Radioactive Waste |  |  |  |
Commitments and Contingencies |  |  |  |
Litigation settlement amount | $ 3,300,000 |  |  |

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- Definition Represents the "all risk" (including nuclear hazards) insurance for property damage to, and decontamination of, property at Palo Verde of which a substantial portion must first be applied to stabilization and decontamination. + References No definition available. + Details
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