Long-Term Debt and Liquidity Matters - Components of Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Long-Term Debt and Liquidity Matters [Line Items]
Total long-term debt	$ 8,415,622	$ 7,791,971
Long-term debt less current maturities (Note 6)	7,540,622	7,741,286
Pinnacle West
Long-Term Debt and Liquidity Matters [Line Items]
Gross long-term debt	8,468,975
Unamortized discount	(15)	(25)
Unamortized debt issuance cost	(1,254)	(2,083)
Total long-term debt	1,123,731	947,892
Less current maturities	625,000	0
Total long-term debt less current maturities	498,731	947,892
Long-term debt less current maturities (Note 6)	498,731	947,892
Arizona Public Service Company
Long-Term Debt and Liquidity Matters [Line Items]
Gross long-term debt	7,343,975
Unamortized discount	(14,197)	(14,548)
Unamortized premium	11,162	12,368
Unamortized debt issuance cost	(49,049)	(48,266)
Total long-term debt	7,291,891	6,793,529
Less current maturities	250,000	0
Total long-term debt less current maturities	7,041,891	6,793,529
Long-term debt less current maturities (Note 6)	7,041,891	6,793,529
Bright Canyon Energy Corporation
Long-Term Debt and Liquidity Matters [Line Items]
Los Alamitos equity bridge loan	0	27,575
Los Alamitos construction facility	0	23,110
Unamortized debt issuance cost	0	(135)
Total long-term debt	0	50,550
Less current maturities	0	50,685
Total long-term debt less current maturities	0	(135)
Pollution Control Bonds - Variable | Arizona Public Service Company
Long-Term Debt and Liquidity Matters [Line Items]
Gross long-term debt	$ 163,975	$ 163,975
Weighted-average interest rate (as a percent)	4.11%	3.96%
Total Pollution Control Bonds | Arizona Public Service Company
Long-Term Debt and Liquidity Matters [Line Items]
Gross long-term debt	$ 163,975	$ 163,975
Senior Unsecured Notes | Pinnacle West
Long-Term Debt and Liquidity Matters [Line Items]
Gross long-term debt	$ 500,000	500,000
Interest rate (as a percent)	1.30%
Senior Unsecured Notes | Arizona Public Service Company
Long-Term Debt and Liquidity Matters [Line Items]
Gross long-term debt	$ 7,180,000	6,680,000
Senior Unsecured Notes | Arizona Public Service Company | Minimum
Long-Term Debt and Liquidity Matters [Line Items]
Interest rate (as a percent)	2.20%
Senior Unsecured Notes | Arizona Public Service Company | Maximum
Long-Term Debt and Liquidity Matters [Line Items]
Interest rate (as a percent)	6.88%
Term Loan | Pinnacle West
Long-Term Debt and Liquidity Matters [Line Items]
Term loans	$ 625,000	$ 450,000
Term Loan | Arizona Public Service Company
Long-Term Debt and Liquidity Matters [Line Items]
Weighted-average interest rate (as a percent)	6.20%	5.10%