|**Lines of Credit and Short-Term Borrowings (Tables)**                           | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
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|**Lines of Credit and Short-Term Borrowings**                                    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Schedule of consolidated credit facilities and amounts available and outstanding | The table below presents the consolidated credit facilities and the amounts available and outstanding (dollars in thousands):December 31, 2021December 31, 2020Pinnacle WestAPSTotalPinnacle WestAPSTotalCommitments under Credit Facilities$200,000$1,000,000$1,200,000$231,000$1,000,000$1,231,000Outstanding Commercial Paper, Term Loan and Revolving Credit Facility Borrowings(13,300)(278,700)(292,000)(169,000)—(169,000)Amount of Credit Facilities Available$186,700$721,300$908,000$62,000$1,000,000$1,062,000Commitment Fees0.175%0.125%0.125%0.100%
|                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|                                                                                 | December 31, 2021                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|                                                                                 | Pinnacle West                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
|Commitments under Credit Facilities                                              | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Outstanding Commercial Paper, Term Loan and Revolving Credit Facility Borrowings | (13,300)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Amount of Credit Facilities Available                                            | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Commitment Fees                                                                  | 0.175%                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          

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