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Commitments and Contingencies - Additional Information (Details) $ in Thousands |  |  |  |  |  |  |  |  | 1 Months Ended | 12 Months Ended | 132 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jan. 01, 2024 USD ($) trust | Oct. 31, 2023 claim | Jan. 17, 2023 USD ($) | Sep. 30, 2022 USD ($) | Nov. 02, 2021 USD ($) | Jul. 03, 2018 USD ($) | Jul. 06, 2016 | Aug. 14, 2014 USD ($) | Feb. 29, 2024 USD ($) | Dec. 31, 2023 USD ($) trust MW | Dec. 31, 2022 USD ($) | Jun. 30, 2022 timePeriod claim | Apr. 18, 2023 USD ($)
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Coal mine reclamation |  |  |  |  |  |  |  |  |  | $ 184,007 | $ 179,255 |  |
Non-recourse construction financing agreement |  |  |  |  |  |  |  |  |  |  |  |  | $ 140,000
Financing agreement of sponsor equity |  |  |  |  |  |  |  |  |  |  |  |  | $ 40,000
Production tax credit guarantees |  |  |  |  |  |  |  |  |  | $ 31,000 |  |  |
Kūpono Solar |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Project plant capacity (in MW's) | MW |  |  |  |  |  |  |  |  |  | 42 |  |  |
Asset purchase power agreement |  |  |  |  |  |  |  |  |  | 20 years |  |  |
Arizona Public Service Company |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Number of VIE lessor trusts | trust |  |  |  |  |  |  |  |  |  | 3 |  |  |
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 |  |  |  |  |  |  |  |  |  | 22,400 |  |  |
Collateral assurance based on rating triggers |  |  |  |  |  |  |  |  |  | $ 62,600 |  |  |
Period to provide collateral assurance based on rating triggers |  |  |  |  |  |  |  |  |  | 20 days |  |  |
2024 |  |  |  |  |  |  |  |  |  | $ 1,034,000 |  |  |
2025 |  |  |  |  |  |  |  |  |  | 1,190,000 |  |  |
2026 |  |  |  |  |  |  |  |  |  | 1,310,000 |  |  |
2027 |  |  |  |  |  |  |  |  |  | 1,284,000 |  |  |
2028 |  |  |  |  |  |  |  |  |  | 1,292,000 |  |  |
Thereafter |  |  |  |  |  |  |  |  |  | 14,700,000 |  |  |
Coal mine reclamation |  |  |  |  |  |  |  |  |  | 184,007 | 179,255 |  |
Arizona Public Service Company | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum insurance against public liability per occurrence for a nuclear incident | $ 16,300,000 |  |  |  |  |  |  |  |  |  |  |  |
Maximum available nuclear liability insurance | 500,000 |  |  |  |  |  |  |  |  |  |  |  |
Remaining nuclear liability insurance through mandatory industry wide retrospective assessment program | 15,800,000 |  |  |  |  |  |  |  |  |  |  |  |
Maximum assessment per reactor for each nuclear incident | 165,900 |  |  |  |  |  |  |  |  |  |  |  |
Annual limit per incident with respect to maximum assessment | $ 24,700 |  |  |  |  |  |  |  |  |  |  |  |
Number of VIE lessor trusts | trust | 3 |  |  |  |  |  |  |  |  |  |  |  |
Maximum potential retrospective assessment per incident of APS | $ 144,900 |  |  |  |  |  |  |  |  |  |  |  |
Annual payment limitation with respect to maximum potential retrospective assessment | $ 21,600 |  |  |  |  |  |  |  |  |  |  |  |
Arizona Public Service Company | Surety Bonds Expiring in 2025 |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Surety bonds expiring, amount |  |  |  |  |  |  |  |  |  | 20,000 |  |  |
Arizona Public Service Company | Letter of Credit |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Outstanding letters of credit |  |  |  |  |  |  |  |  |  | 27,000 |  |  |
Arizona Public Service Company | SCE | Four Corners Units 4 and 5 |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Disallowance of plant investments |  |  |  |  | $ 194,000 |  |  |  |  |  |  |  |
Cost deferrals |  |  |  |  | $ 215,500 |  |  |  |  |  |  |  |
Arizona Public Service Company | Contaminated Groundwater Wells |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Costs related to investigation and study under Superfund site |  |  |  |  |  |  |  |  |  | 3,000 |  |  |
Remedial investigation work |  |  | $ 1,700 |  |  |  |  |  |  |  |  |  |
Arizona Public Service Company | Contaminated Groundwater Wells | Pending Litigation |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Settlement amount |  |  |  | $ 20,700 |  |  |  |  |  |  |  |  |
Arizona Public Service Company | Renewable Energy Credits |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
2024 |  |  |  |  |  |  |  |  |  | 29,000 |  |  |
2025 |  |  |  |  |  |  |  |  |  | 27,000 |  |  |
2026 |  |  |  |  |  |  |  |  |  | 24,000 |  |  |
2027 |  |  |  |  |  |  |  |  |  | 20,000 |  |  |
2028 |  |  |  |  |  |  |  |  |  | 17,000 |  |  |
Thereafter |  |  |  |  |  |  |  |  |  | 52,000 |  |  |
Arizona Public Service Company | Coal Mine Reclamation Balance Sheet Obligations |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Coal mine reclamation |  |  |  |  |  |  |  |  |  | 184,000 | 179,000 |  |
Arizona Public Service Company | Coal Mine Reclamation Obligations |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
2024 |  |  |  |  |  |  |  |  |  | 19,000 |  |  |
2025 |  |  |  |  |  |  |  |  |  | 20,000 |  |  |
2026 |  |  |  |  |  |  |  |  |  | 21,000 |  |  |
2027 |  |  |  |  |  |  |  |  |  | 22,000 |  |  |
2028 |  |  |  |  |  |  |  |  |  | 23,000 |  |  |
Thereafter |  |  |  |  |  |  |  |  |  | 2,000 |  |  |
4CA | Four Corners |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage share cost of control |  |  |  |  |  |  | 7.00% |  |  |  |  |  |
NTEC | Four Corners |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Option to purchase, ownership interest (as a percent) |  |  |  |  |  | 7.00% |  |  |  |  |  |  |
Proceeds from operating and maintenance cost reimbursement |  |  |  |  |  | $ 70,000 |  |  |  |  |  |  |
Asset purchase agreement, option to purchase, ownership interest, percentage |  |  |  |  |  | 7.00% |  |  |  |  |  |  |
Bright Canyon Energy Corporation | Clear Creek Wind Farm |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Equity method investments |  |  |  | $ 17,100 |  |  |  |  |  |  | 0 |  |
Impairment of equity method investments |  |  |  |  |  |  |  |  |  |  | $ 12,800 |  |
Arizona Public Service Company and Palo Verde Owners vs. United States Department of Energy - Spent Nuclear Fuel and Waste Disposal |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Settlement amount, awarded to company |  |  |  |  |  |  |  | $ 18,460 |  | 138,200 |  |  |
Arizona Public Service Company and Palo Verde Owners vs. United States Department of Energy - Spent Nuclear Fuel and Waste Disposal | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Settlement amount, awarded to company |  |  |  |  |  |  |  |  | $ 18,390 |  |  |  |
Arizona Public Service Company and Palo Verde Owners vs. United States Department of Energy - Spent Nuclear Fuel and Waste Disposal | Arizona Public Service Company |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Commitments and Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Gain contingency, new claims filed, number | claim |  | 10 |  |  |  |  |  |  |  |  |  | 9 |
Gain contingency, number of settlement agreement time periods | timePeriod |  |  |  |  |  |  |  |  |  |  |  | 9 |
Settlement amount, awarded to company |  |  |  |  |  |  |  | $ 5,400 |  | $ 40,200 |  |  |

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