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Retirement Plans and Other Postretirement Benefits - Additional Information (Details) - USD ($)
12 Months Ended
Jan. 04, 2021
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]          
Ultimate healthcare cost trend rate (pre-65 participants)   4.75% 4.75%   4.75%
Initial and ultimate healthcare cost trend rate (post-65 participants) (a)   2.00% 2.00%    
Funded percentage (more than)   100.00% 100.00%    
Partnership funding commitments, contribution amount (up to)   $ 50,000,000      
Partnership funding commitments, funded amount   38,000,000      
Other Benefits          
Defined Benefit Plan Disclosure [Line Items]          
Transfer to active union medical account $ 106,000,000 $ 0 $ 105,852,000    
Expected long-term return on plan assets for next fiscal year (as a percent)   6.95%      
Contributions          
Employer contributions   $ 0 0    
Minimum contributions under MAP-21          
Retiree medical cost reimbursement   26,000,000 24,000,000 $ 26,000,000  
Pension Benefits          
Defined Benefit Plan Disclosure [Line Items]          
Transfer to active union medical account $ (106,000,000) $ 0 0    
Expected long-term return on plan assets for next fiscal year (as a percent)   6.70%      
Contributions          
Employer contributions   $ 0 100,000,000 100,000,000  
Minimum contributions under MAP-21          
Minimum contributions under MAP-21   0      
Pinnacle West          
Minimum contributions under MAP-21          
Expenses recorded for the defined contribution savings plan   $ 12,000,000 $ 12,000,000 $ 11,000,000  
Arizona Public Service Company          
Minimum contributions under MAP-21          
APS's employees share of total cost of the plans (as a percent)   99.00%