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Commitments and Contingencies - Palo Verde Nuclear Generating Station and Contractual Obligations (Details) |  |  | 9 Months Ended | 84 Months Ended |
--- | --- | --- | --- | --- | ---
Feb. 11, 2020 USD ($) | Oct. 31, 2019 USD ($) | Sep. 30, 2020 USD ($) power_plant | Jun. 30, 2018 USD ($) claim time_period | 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 | $ 15,400,000 | $ 16,000,000 |  | $ 84,300,000 |
APS |  |  |  |  |
Commitments and Contingencies |  |  |  |  |
Maximum insurance against public liability per occurrence for a nuclear incident (up to) |  |  | $ 13,800,000,000 |  |
Maximum available nuclear liability insurance (up to) |  |  | 450,000,000 |  |
Remaining nuclear liability insurance through mandatory industry wide retrospective assessment program |  |  | 13,300,000,000 |  |
Maximum retrospective premium assessment per reactor for each nuclear liability incident |  |  | 137,600,000 |  |
Annual limit per incident with respect to maximum retrospective premium assessment |  |  | $ 20,500,000 |  |
Number of VIE lessor trusts |  |  | 3 |  | 3
Maximum potential retrospective assessment per incident of APS |  |  | $ 120,100,000 |  |
Annual payment limitation with respect to maximum potential retrospective premium assessment |  |  | 17,900,000 |  |
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 |  |  | 25,800,000 |  |
Collateral assurance provided based on rating triggers |  |  | $ 75,100,000 |  |
Period to provide collateral assurance based on rating triggers |  |  | 20 days |  |
APS | Public Utilities, Inventory, Fuel |  |  |  |  |
Commitments and Contingencies |  |  |  |  |
Purchase obligation |  |  | $ 600,000,000 |  |
APS | Breach of Contract for Disposal of Spent Nuclear Fuel and/or High Level Radioactive Waste |  |  |  |  |
Commitments and Contingencies |  |  |  |  |
Litigation settlement amount | $ 4,500,000 | $ 4,700,000 |  | $ 24,500,000 |
Number of claims submitted | claim |  |  |  | 5 |
Number of settlement agreement time periods | time_period |  |  |  | 5 |

X
- 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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- Definition Represents the annual limit per incident with respect to the maximum assessment per reactor under the program for each nuclear incident, to be periodically adjusted for inflation. + References No definition available. + Details
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