v3.25.1
Common Stock Equity and Earnings Per Share - Additional Information (Details)
$ / shares in Units, $ in Millions
1 Months Ended 3 Months Ended
Jun. 30, 2024
USD ($)
day
Mar. 31, 2025
USD ($)
agreement
$ / shares
Nov. 08, 2024
USD ($)
Subsidiary or Equity Method Investee [Line Items]      
Unsettled proceeds   $ 100  
Convertible Notes Due Maturing June 2027 | Convertible Debt      
Subsidiary or Equity Method Investee [Line Items]      
Debt instrument, convertible, conversion ratio   0.0108338  
Pinnacle West | Convertible Notes Due Maturing June 2027 | Convertible Debt      
Subsidiary or Equity Method Investee [Line Items]      
Notes issued $ 525    
Interest rate (as a percent) 4.75%    
Debt instrument, convertible, conversion price (in usd per share) | $ / shares   $ 92.30  
Debt instrument redemption price percentage   100.00%  
Long-term debt   $ 525  
Unamortized debt issuance expense   6  
Convertible debt, fair value   591  
Pinnacle West | Convertible Notes Due Maturing June 2027 | Convertible Debt | Debt Conversion Terms One      
Subsidiary or Equity Method Investee [Line Items]      
Debt instrument, convertible, threshold trading days | day 20    
Debt instrument, convertible, threshold consecutive trading days | day 30    
Debt instrument, convertible, threshold percentage of stock price trigger 130.00%    
Pinnacle West | Convertible Notes Due Maturing June 2027 | Convertible Debt | Debt Conversion Terms Two      
Subsidiary or Equity Method Investee [Line Items]      
Debt instrument, convertible, threshold trading days | day 5    
Debt instrument, convertible, threshold consecutive trading days | day 10    
Debt instrument, convertible, threshold percentage of stock price trigger 98.00%    
ATM Program      
Subsidiary or Equity Method Investee [Line Items]      
Value of shares to be issued under ATM program   $ 800 $ 900
At the Market Offering      
Subsidiary or Equity Method Investee [Line Items]      
Number of outstanding forward sale agreements | agreement   2