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Commitments and Contingencies - Additional Information (Details) $ in Thousands |  |  |  |  |  |  |  | 9 Months Ended | 12 Months Ended | 108 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Oct. 31, 2022 claim | Sep. 30, 2022 USD ($) | Nov. 02, 2021 USD ($) | Nov. 01, 2021 USD ($) | Feb. 22, 2021 USD ($) | Jul. 03, 2018 USD ($) | Jul. 06, 2016 | Sep. 30, 2022 USD ($) | Dec. 31, 2022 USD ($) Trust | Jun. 30, 2020 USD ($) timePeriod claim | Feb. 11, 2022 USD ($)
Financial Assurances |  |  |  |  |  |  |  |  |  |  |
Production tax credit guarantees |  |  |  |  |  |  |  |  | $ 34,000 |  |
Arizona Public Service Company |  |  |  |  |  |  |  |  |  |  |
Palo Verde Nuclear Generating Station [Abstract] |  |  |  |  |  |  |  |  |  |  |
Maximum insurance against public liability per occurrence for a nuclear incident |  |  |  |  |  |  |  |  | 13,700,000 |  |
Maximum available nuclear liability insurance |  |  |  |  |  |  |  |  | 450,000 |  |
Remaining nuclear liability insurance through mandatory industry wide retrospective assessment program |  |  |  |  |  |  |  |  | 13,200,000 |  |
Maximum assessment per reactor for each nuclear incident |  |  |  |  |  |  |  |  | 137,600 |  |
Annual limit per incident with respect to maximum assessment |  |  |  |  |  |  |  |  | $ 20,500 |  |
Number of VIE lessor trusts | Trust |  |  |  |  |  |  |  |  | 3 |  |
Maximum potential retrospective assessment per incident of APS |  |  |  |  |  |  |  |  | $ 120,100 |  |
Annual payment limitation with respect to maximum potential retrospective assessment |  |  |  |  |  |  |  |  | 17,900 |  |
Amount of "all risk" (including nuclear hazards) insurance for property damage to, and decontamination of, property at Palo Verde |  |  |  |  |  |  |  |  | 2,800,000 |  |
Request second-year energy price for exported energy |  |  |  |  |  |  |  |  | 22,300 |  |
Collateral assurance based on rating triggers |  |  |  |  |  |  |  |  | $ 62,800 |  |
Period to provide collateral assurance based on rating triggers |  |  |  |  |  |  |  |  | 20 days |  |
Arizona Public Service Company | Contaminated Groundwater Wells |  |  |  |  |  |  |  |  |  |  |
Palo Verde Nuclear Generating Station [Abstract] |  |  |  |  |  |  |  |  |  |  |
Costs claimed |  |  |  |  |  |  |  | $ 21,000 |  |  |
Arizona Public Service Company | Pending Litigation | Contaminated Groundwater Wells |  |  |  |  |  |  |  |  |  |  |
Arizona Attorney General [Abstract] |  |  |  |  |  |  |  |  |  |  |
Settlement amount |  | $ 20,700 |  |  |  |  |  |  |  |  |
Bright Canyon Energy Corporation | Clear Creek Wind Farm |  |  |  |  |  |  |  |  |  |  |
BCE Matters [Abstract] |  |  |  |  |  |  |  |  |  |  |
Equity method investments |  | $ 17,100 |  |  |  |  |  | $ 17,100 | $ 0 |  |
Impairment of equity method investments |  |  |  |  |  |  |  |  | 12,800 |  |
2017 Settlement Agreement and its Customer Education and Outreach Plan | Arizona Public Service Company |  |  |  |  |  |  |  |  |  |  |
Arizona Attorney General [Abstract] |  |  |  |  |  |  |  |  |  |  |
Settlement amount |  |  |  |  | $ 24,750 |  |  |  |  |  |
Settlement amount returned to customers |  |  |  |  | $ 24,000 |  |  |  |  |  |
Arizona Public Service Company and Palo Verde Owners vs. United States Department of Energy - Spent Nuclear Fuel and Waste Disposal |  |  |  |  |  |  |  |  |  |  |
Palo Verde Nuclear Generating Station [Abstract] |  |  |  |  |  |  |  |  |  |  |
Settlement amount, awarded to company |  |  |  | $ 14,300 |  |  |  |  |  | $ 123,900 |
Arizona Public Service Company and Palo Verde Owners vs. United States Department of Energy - Spent Nuclear Fuel and Waste Disposal | Arizona Public Service Company |  |  |  |  |  |  |  |  |  |  |
Palo Verde Nuclear Generating Station [Abstract] |  |  |  |  |  |  |  |  |  |  |
Gain contingency, new claims filed, number | claim | 9 |  |  |  |  |  |  |  |  | 8 |
Gain contingency, number of settlement agreement time periods | timePeriod |  |  |  |  |  |  |  |  |  | 8 |
Settlement amount, awarded to company |  |  |  | $ 4,200 |  |  |  |  |  | $ 36,000 |
Letter of Credit | Arizona Public Service Company |  |  |  |  |  |  |  |  |  |  |
Financial Assurances |  |  |  |  |  |  |  |  |  |  |
Outstanding letters of credit |  |  |  |  |  |  |  |  | 10,000 |  |
Bridge Loan | Bright Canyon Energy Corporation | Pinnacle West |  |  |  |  |  |  |  |  |  |  |
Financial Assurances |  |  |  |  |  |  |  |  |  |  |
Debt guarantee |  |  |  |  |  |  |  |  |  |  | $ 42,000
Four Corners Units 4 and 5 | Arizona Public Service Company | SCE |  |  |  |  |  |  |  |  |  |  |
Four Corners SCR Cost Recovery [Abstract] |  |  |  |  |  |  |  |  |  |  |
Disallowance of plant investments |  |  | $ 194,000 |  |  |  |  |  |  |  |
Cost deferrals |  |  | $ 215,500 |  |  |  |  |  |  |  |
Amount not recoverable |  |  |  |  |  |  |  |  | $ 154,400 |  |
Four Corners | NTEC |  |  |  |  |  |  |  |  |  |  |
Environmental Matters |  |  |  |  |  |  |  |  |  |  |
Option to purchase, ownership interest (as a percent) |  |  |  |  |  | 7.00% | 7.00% |  |  |  |
Payment received for coal supply agreement |  |  |  |  |  | $ 70,000 |  |  |  |  |
Financial Assurances |  |  |  |  |  |  |  |  |  |  |
Option to purchase, ownership interest (as a percent) |  |  |  |  |  | 7.00% |  |  |  |  |
Four Corners | 4CA |  |  |  |  |  |  |  |  |  |  |
Environmental Matters |  |  |  |  |  |  |  |  |  |  |
Percentage share cost of control |  |  |  |  |  |  | 7.00% |  |  |  |
Regional Haze Rules | Four Corners Units 4 and 5 | Arizona Public Service Company |  |  |  |  |  |  |  |  |  |  |
Environmental Matters |  |  |  |  |  |  |  |  |  |  |
Percentage share cost of control |  |  |  |  |  |  |  |  | 63.00% |  |
Expected environmental cost |  |  |  |  |  |  |  |  | $ 400,000 |  |
Regional Haze Rules | Four Corners Units 4 and 5 | Four Corners | Arizona Public Service Company |  |  |  |  |  |  |  |  |  |  |
Environmental Matters |  |  |  |  |  |  |  |  |  |  |
Additional expected environment cost |  |  |  |  |  |  |  |  | $ 45,000 |  |
Regional Haze Rules | Four Corners Units 4 and 5 | Natural Gas Tolling Letter of Credit | Arizona Public Service Company |  |  |  |  |  |  |  |  |  |  |
Environmental Matters |  |  |  |  |  |  |  |  |  |  |
Additional percentage share of cost of control |  |  |  |  |  |  |  |  | 7.00% |  |
Coal Combustion Waste | Four Corners | Arizona Public Service Company |  |  |  |  |  |  |  |  |  |  |
Environmental Matters |  |  |  |  |  |  |  |  |  |  |
Additional expected environment cost |  |  |  |  |  |  |  |  | $ 30,000 |  |
Coal Combustion Waste | Navajo Generating Station | Arizona Public Service Company |  |  |  |  |  |  |  |  |  |  |
Environmental Matters |  |  |  |  |  |  |  |  |  |  |
Additional expected environment cost |  |  |  |  |  |  |  |  | 1,000 |  |
Coal Combustion Waste | Minimum | Cholla | Arizona Public Service Company |  |  |  |  |  |  |  |  |  |  |
Environmental Matters |  |  |  |  |  |  |  |  |  |  |
Additional expected environment cost |  |  |  |  |  |  |  |  | 16,000 |  |
Coal Combustion Waste | Minimum | Cholla and Four Corners | Arizona Public Service Company |  |  |  |  |  |  |  |  |  |  |
Environmental Matters |  |  |  |  |  |  |  |  |  |  |
Additional expected environment cost |  |  |  |  |  |  |  |  | 10,000 |  |
Coal Combustion Waste | Maximum | Cholla and Four Corners | Arizona Public Service Company |  |  |  |  |  |  |  |  |  |  |
Environmental Matters |  |  |  |  |  |  |  |  |  |  |
Additional expected environment cost |  |  |  |  |  |  |  |  | 15,000 |  |
Surety Bonds Expiring in 2025 | Arizona Public Service Company |  |  |  |  |  |  |  |  |  |  |
Financial Assurances |  |  |  |  |  |  |  |  |  |  |
Surety bonds expiring, amount |  |  |  |  |  |  |  |  | $ 8,000 |  |

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