Investments in Nuclear Decommissioning Trusts and Other Special Use Funds (Details) - Arizona Public Service Company - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Nuclear decommissioning trust fund assets
Fair Value	$ 1,564,027	$ 1,420,641
Total Unrealized Gains	358,112	337,994
Total Unrealized Losses	(40,868)	(69,091)
Amortized cost	1,120,000	927,000
Realized gains and losses and proceeds from the sale of securities by the nuclear decommissioning trust funds
Realized gains	112,094	9,437	$ 134,659
Realized losses	(41,780)	(40,239)	(8,438)
Proceeds from the sale of securities	1,679,722	1,207,197	1,720,966
Nuclear Decommissioning Trusts
Nuclear decommissioning trust fund assets
Fair Value	1,201,246	1,073,410
Realized gains and losses and proceeds from the sale of securities by the nuclear decommissioning trust funds
Realized gains	111,922	9,017	134,610
Realized losses	(41,212)	(40,239)	(8,431)
Proceeds from the sale of securities	1,324,978	979,639	1,457,305
Other Special Use Funds
Nuclear decommissioning trust fund assets
Fair Value	362,781	347,231
Realized gains and losses and proceeds from the sale of securities by the nuclear decommissioning trust funds
Realized gains	172	420	49
Realized losses	(568)	0	(7)
Proceeds from the sale of securities	354,744	227,558	$ 263,661
Equity securities
Nuclear decommissioning trust fund assets
Equity securities	461,671	554,214
Total Unrealized Gains	336,555	334,817
Total Unrealized Losses	0	(267)
Equity securities | Nuclear Decommissioning Trusts
Nuclear decommissioning trust fund assets
Equity securities	420,680	487,240
Equity securities | Other Special Use Funds
Nuclear decommissioning trust fund assets
Equity securities	40,991	66,974
Available for sale-fixed income securities
Nuclear decommissioning trust fund assets
Fair Value	1,100,927	861,637
Total Unrealized Gains	21,518	3,177
Total Unrealized Losses	(40,868)	(68,795)
Fair value of fixed income securities, summarized by contractual maturities
Less than one year	121,606
1 year – 5 years	424,772
5 years – 10 years	201,452
Greater than 10 years	353,097
Total	1,100,927
Available for sale-fixed income securities | Nuclear Decommissioning Trusts
Nuclear decommissioning trust fund assets
Fair Value	781,333	582,343
Fair value of fixed income securities, summarized by contractual maturities
Less than one year	26,057
1 year – 5 years	225,891
5 years – 10 years	176,288
Greater than 10 years	353,097
Total	781,333
Available for sale-fixed income securities | Other Special Use Funds
Nuclear decommissioning trust fund assets
Fair Value	319,594	279,294
Available for sale-fixed income securities | Coal Reclamation Escrow Account
Fair value of fixed income securities, summarized by contractual maturities
Less than one year	58,692
1 year – 5 years	46,120
5 years – 10 years	0
Greater than 10 years	0
Total	104,812
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	36,857
1 year – 5 years	152,761
5 years – 10 years	25,164
Greater than 10 years	0
Total	214,782
Other
Nuclear decommissioning trust fund assets
Fair Value	1,429	4,790
Total Unrealized Gains	39	0
Total Unrealized Losses	0	(29)
Other | Nuclear Decommissioning Trusts
Nuclear decommissioning trust fund assets
Fair Value	(767)	3,827
Other | Other Special Use Funds
Nuclear decommissioning trust fund assets
Fair Value	$ 2,196	$ 963