Income Taxes - Components of Income Tax Expense (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current:
Federal									$ 8,630	$ (12,335)	$ 25,054
State									1,259	4,763	10,382
Total current									9,889	(7,572)	35,436
Deferred:
Federal									201,743	221,505	167,365
State									24,779	23,787	17,904
Total deferred									226,522	245,292	185,269
Income tax expense	$ 27,309	$ 141,446	$ 65,742	$ 1,914	$ 22,847	$ 139,555	$ 67,371	$ 7,947	236,411	237,720	220,705
ARIZONA PUBLIC SERVICE COMPANY
Current:
Federal									711	6,485	40,115
State									4,276	7,813	15,598
Total current									4,987	14,298	55,713
Deferred:
Federal									215,178	208,326	165,027
State									25,677	23,217	16,620
Total deferred									240,855	231,543	181,647
Income tax expense									$ 245,842	$ 245,841	$ 237,360