Long-Term Debt and Liquidity Matters - Fair Value of Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Estimated fair value of long-term debt, including current maturities
Carrying Amount	$ 7,063,735	$ 6,314,266
Fair Value	7,726,354	7,612,841
Arizona Public Service Company
Estimated fair value of long-term debt, including current maturities
Carrying Amount	6,266,693	5,817,945
Fair Value	6,933,619	7,103,791
Pinnacle West
Estimated fair value of long-term debt, including current maturities
Carrying Amount	797,042	496,321
Fair Value	$ 792,735	$ 509,050