Long-Term Debt and Liquidity Matters - Fair Value of Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Estimated fair value of long-term debt, including current maturities
Carrying Amount	$ 8,415,622	$ 7,791,971
Fair Value	7,555,653	6,585,701
Arizona Public Service Company
Estimated fair value of long-term debt, including current maturities
Carrying Amount	7,291,891	6,793,529
Fair Value	6,459,718	5,629,491
Bright Canyon Energy Corporation
Estimated fair value of long-term debt, including current maturities
Carrying Amount	0	50,550
Fair Value	0	50,685
Pinnacle West
Estimated fair value of long-term debt, including current maturities
Carrying Amount	1,123,731	947,892
Fair Value	$ 1,095,935	$ 905,525