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Regulatory Matters - Additional Information (Details) |  |  |  |  |  |  |  |  |  |  |  | 1 Months Ended | 10 Months Ended | 12 Months Ended |  |
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Dec. 17, 2021 USD ($) | Nov. 02, 2021 USD ($) | Oct. 27, 2021 USD ($) | Oct. 01, 2021 $ / kWh | Feb. 22, 2021 USD ($) | Jan. 21, 2021 USD ($) | Aug. 20, 2020 USD ($) Customer | May 01, 2020 $ / kWh | Nov. 14, 2019 USD ($) Customer | May 01, 2019 $ / kWh | Dec. 20, 2016 | Sep. 30, 2018 USD ($) | Apr. 30, 2018 USD ($) | Dec. 31, 2020 | Dec. 31, 2020 program MW | Dec. 31, 2021 USD ($) | Aug. 02, 2021
Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of customers | Customer |  |  |  |  |  |  | 3,800 |  | 13,000 |  |  |  |  |  |  |  |
Inconvenience payment |  |  |  |  |  |  | $ 25 |  | $ 25 |  |  |  |  |  |  |  |
Arizona Public Service Company | Retired power plant costs |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory asset, net book value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 41,800,000 |
Arizona Public Service Company | Navajo plant |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory asset, net book value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 62,200,000 |
Arizona Public Service Company | Navajo plant, coal reclamation regulatory asset |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory asset, net book value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 16,800,000 |
Arizona Public Service Company | SCE | Four Corners Units 4 and 5 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Settlement agreement, ACC approved rate adjustment, annualized customer impact |  |  |  |  |  |  |  |  |  |  |  | $ 58,500,000 | $ 67,500,000 |  |  |  |
Recommended rate adjustment, annualized customer impact, disallowance of investments |  | $ 194,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Recommended rate adjustment, annualized customer impact, cost deferrals |  | $ 215,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potential charges |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 154,400,000 |
Arizona Public Service Company | 2017 Settlement Agreement and its Customer Education and Outreach Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Settlement amount |  |  |  |  | $ 24,750,000 |  |  |  |  |  |  |  |  |  |  |  |
Settlement amount returned to customers |  |  |  |  | $ 24,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Arizona Public Service Company | Damage from Fire, Explosion or Other Hazard |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Customer support fund, payment period |  |  |  |  |  | 8 months |  |  |  |  |  |  |  | 8 months |  |  |
Past due balance threshold qualifying for payment extension |  |  |  |  |  | $ 75 |  |  |  |  |  |  |  |  |  |  |
ACC | Arizona Public Service Company |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of public utility programs | program |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 |  |
Program term |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 18 years |  |
Solar power capacity | MW |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 80 |  |
Net Metering | ACC | Arizona Public Service Company |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cost of service, resource comparison proxy method, maximum annual percentage decrease |  |  |  |  |  |  |  |  |  |  | 10.00% |  |  |  |  |  |
Cost of service for interconnected DG system customers, grandfathered period |  |  |  |  |  |  |  |  |  |  | 20 years |  |  |  |  |  |
Guaranteed export price period |  |  |  |  |  |  |  |  |  |  | 10 years |  |  |  |  |  |
Request second-year energy price for exported energy | $ / kWh |  |  |  | 0.094 |  |  |  | 0.094 |  | 0.105 |  |  |  |  |  |  |
Retail Rate Case Filing with Arizona Corporation Commission | ACC | Arizona Public Service Company | Navajo Nation, Hopi Tribe | Coal Community Transition Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Recommended rate adjustment, annualized customer impact, cost deferrals |  |  | $ 215,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Retail Rate Case Filing with Arizona Corporation Commission | ACC | Arizona Public Service Company | Navajo Nation, Economic Development Organization | Coal Community Transition Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disallowance of annual amortization percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 15.00%
Retail Rate Case Filing with Arizona Corporation Commission | ACC | Arizona Public Service Company | Navajo Nation Reservation | Coal Community Transition Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Recommended rate adjustment, annualized customer impact, disallowance of investments | $ 215,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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