Long-Term Debt and Liquidity Matters - Estimated Fair Value of Long-Term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Estimated fair value of long-term debt, including current maturities
Carrying Amount	$ 8,414,372	$ 7,791,971
Fair Value	7,057,297	6,585,701
APS
Estimated fair value of long-term debt, including current maturities
Carrying Amount	7,290,851	6,793,529
Fair Value	5,969,892	5,629,491
BCE
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	1,123,521	947,892
Fair Value	$ 1,087,405	$ 905,525