Income Taxes - Components of Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current:
Federal	$ 11,869	$ (13,551)	$ 18,375
State	1,932	3,195	3,342
Total current	13,801	(10,356)	21,717
Deferred:
Federal	53,398	(14,982)	94,721
State	10,974	9,565	17,464
Total deferred	64,372	(5,417)	112,185
Income tax expense/(benefit)	78,173	(15,773)	133,902
ARIZONA PUBLIC SERVICE COMPANY
Current:
Federal	57,299	(54,697)	88,180
State	99	695	1,877
Total current	57,398	(54,002)	90,057
Deferred:
Federal	15,122	29,321	32,436
State	16,244	15,109	22,321
Total deferred	31,366	44,430	54,757
Income tax expense/(benefit)	$ 88,764	$ (9,572)	$ 144,814