Income Taxes - Components of Income Tax Expense (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current:
Federal									$ 25,054	$ (81,784)	$ (3,493)
State									10,382	10,537	8,395
Total current									35,436	(71,247)	4,902
Deferred:
Federal									167,365	279,973	200,322
State									17,904	21,865	28,280
Total deferred									185,269	301,838	228,602
Total income tax expense									220,705	230,591	233,504
Less: income tax benefit on discontinued operations									0	0	(3,813)
INCOME TAXES (Note 4)	5,007	134,753	74,540	6,405	9,167	131,912	77,043	12,469	220,705	230,591	237,317
ARIZONA PUBLIC SERVICE COMPANY
Current:
Federal									40,115	(97,531)	(11,650)
State									15,598	11,983	12,308
Total current									55,713	(85,548)	658
Deferred:
Federal									165,027	305,389	216,367
State									16,620	25,254	27,371
Total deferred									181,647	330,643	243,738
Total income tax expense									237,360	245,095	244,396
INCOME TAXES (Note 4)									$ 237,360	$ 245,095	$ 244,396