Investments in Nuclear Decommissioning Trusts and Other Special Use Funds (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Fair value of fixed income securities, summarized by contractual maturities
Cash equivalents	$ 23	$ 10
Nuclear decommissioning trusts (Notes 12 and 18)	1,282,845	1,201,246
Variable Interest Entity | Pinnacle West Captive Insurance Cell
Fair value of fixed income securities, summarized by contractual maturities
Special use fund	34,000	5,000
Equity securities
Fair value of fixed income securities, summarized by contractual maturities
Nuclear decommissioning trusts (Notes 12 and 18)	15,736	10,297
Arizona Public Service Company
Nuclear decommissioning trust fund assets
Fair Value	1,691,202	1,564,027
Total Unrealized Gains	366,844	358,112
Total Unrealized Losses	(32,136)	(40,868)
Amortized cost	1,224,000	1,120,000
Realized gains and losses and proceeds from the sale of securities by the nuclear decommissioning trust funds
Realized gains	76,062	112,094	$ 9,437
Realized losses	(21,966)	(41,780)	(40,239)
Proceeds from the sale of securities	1,686,094	1,679,722	1,207,197
Fair value of fixed income securities, summarized by contractual maturities
Nuclear decommissioning trusts (Notes 12 and 18)	1,282,845	1,201,246
Arizona Public Service Company | Nuclear Decommissioning Trusts
Nuclear decommissioning trust fund assets
Fair Value	1,282,845	1,201,246
Realized gains and losses and proceeds from the sale of securities by the nuclear decommissioning trust funds
Realized gains	75,690	111,922	9,017
Realized losses	(21,966)	(41,212)	(40,239)
Proceeds from the sale of securities	1,330,940	1,324,978	979,639
Arizona Public Service Company | Other Special Use Funds
Nuclear decommissioning trust fund assets
Fair Value	408,357	362,781
Realized gains and losses and proceeds from the sale of securities by the nuclear decommissioning trust funds
Realized gains	372	172	420
Realized losses	0	(568)	0
Proceeds from the sale of securities	355,154	354,744	$ 227,558
Arizona Public Service Company | Equity securities
Nuclear decommissioning trust fund assets
Equity securities	460,432	461,671
Total Unrealized Gains	359,127	336,555
Total Unrealized Losses	(176)	0
Arizona Public Service Company | Equity securities | Nuclear Decommissioning Trusts
Nuclear decommissioning trust fund assets
Equity securities	435,470	420,680
Arizona Public Service Company | Equity securities | Other Special Use Funds
Nuclear decommissioning trust fund assets
Equity securities	24,962	40,991
Arizona Public Service Company | Available for sale-fixed income securities
Nuclear decommissioning trust fund assets
Fair Value	1,199,584	1,100,927
Total Unrealized Gains	7,717	21,518
Total Unrealized Losses	(31,960)	(40,868)
Fair value of fixed income securities, summarized by contractual maturities
Less than one year	146,382
1 year – 5 years	482,340
5 years – 10 years	214,128
Greater than 10 years	356,734
Total	1,199,584
Arizona Public Service Company | Available for sale-fixed income securities | Nuclear Decommissioning Trusts
Nuclear decommissioning trust fund assets
Fair Value	844,040	781,333
Fair value of fixed income securities, summarized by contractual maturities
Less than one year	19,868
1 year – 5 years	268,974
5 years – 10 years	198,464
Greater than 10 years	356,734
Total	844,040
Arizona Public Service Company | Available for sale-fixed income securities | Other Special Use Funds
Nuclear decommissioning trust fund assets
Fair Value	355,544	319,594
Arizona Public Service Company | Available for sale-fixed income securities | Coal Reclamation Escrow Account
Fair value of fixed income securities, summarized by contractual maturities
Less than one year	87,424
1 year – 5 years	58,598
5 years – 10 years	0
Greater than 10 years	0
Total	146,022
Arizona Public Service Company | Available for sale-fixed income securities | Active Union Employee Medical Account
Fair value of fixed income securities, summarized by contractual maturities
Less than one year	39,090
1 year – 5 years	154,768
5 years – 10 years	15,664
Greater than 10 years	0
Total	209,522
Arizona Public Service Company | Other
Nuclear decommissioning trust fund assets
Fair Value	31,186	1,429
Total Unrealized Gains	0	39
Total Unrealized Losses	0	0
Arizona Public Service Company | Other | Nuclear Decommissioning Trusts
Nuclear decommissioning trust fund assets
Fair Value	3,335	(767)
Arizona Public Service Company | Other | Other Special Use Funds
Nuclear decommissioning trust fund assets
Fair Value	27,851	$ 2,196
Pinnacle West | Variable Interest Entity | Pinnacle West Captive Insurance Cell
Fair value of fixed income securities, summarized by contractual maturities
Special use fund	$ 34,000