Debt and Liquidity Matters - Schedule of Estimated Fair Value of Long-Term Debt, Including Current Maturities (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Long-Term Debt and Liquidity Matters [Line Items]
Carrying Amount	$ 10,401,675	$ 9,805,676
Fair Value	9,631,021	9,164,530
APS
Long-Term Debt and Liquidity Matters [Line Items]
Carrying Amount	8,734,756	8,139,940
Fair Value	7,874,786	7,433,142
Pinnacle West
Long-Term Debt and Liquidity Matters [Line Items]
Carrying Amount	1,666,919	1,665,736
Fair Value	$ 1,756,235	$ 1,731,388