Selected Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Selected Quarterly Financial Information [Line Items]
OPERATING REVENUES	$ 734,430	$ 1,199,146	$ 890,648	$ 671,219	$ 726,450	$ 1,172,667	$ 906,264	$ 686,251	$ 3,495,443	$ 3,491,632	$ 3,454,628
Operations and maintenance	222,019	220,449	210,965	214,944	260,503	223,418	211,222	212,882	868,377	908,025	924,727
Operating income	109,834	445,111	231,973	67,684	60,184	421,775	254,113	75,170	854,602	811,242	846,323
INCOME TAXES (Note 4)	22,847	139,555	67,371	7,947	5,007	134,753	74,540	6,405	237,720	220,705	230,591
Net income	45,978	261,978	127,507	20,727	9,535	248,086	141,384	24,691	456,190	423,696	439,966
NET INCOME ATTRIBUTABLE TO COMMON SHAREHOLDERS	$ 41,117	$ 257,116	$ 122,902	$ 16,122	$ 5,410	$ 243,961	$ 132,458	$ 15,766	$ 437,257	$ 397,595	$ 406,074
EARNINGS PER WEIGHTED-AVERAGE COMMON SHARE OUTSTANDING
Net income attributable to common shareholders - basic (in dollars per share)	$ 0.37	$ 2.32	$ 1.11	$ 0.15	$ 0.05	$ 2.20	$ 1.20	$ 0.14	$ 3.94	$ 3.59	$ 3.69
Net income attributable to common shareholders — diluted (in dollars per share)	$ 0.37	$ 2.30	$ 1.10	$ 0.14	$ 0.05	$ 2.20	$ 1.19	$ 0.14	$ 3.92	$ 3.58	$ 3.66
ARIZONA PUBLIC SERVICE COMPANY
Selected Quarterly Financial Information [Line Items]
Operating revenues	$ 733,586	$ 1,198,380	$ 889,723	$ 670,668	$ 725,633	$ 1,172,190	$ 905,578	$ 685,545	$ 3,492,357	$ 3,488,946	$ 3,451,251
Operations and maintenance	219,146	216,011	208,031	209,947	253,668	212,430	208,059	208,285	853,135	882,442	897,824
Operating income	86,709	301,238	162,704	61,333	54,835	287,928	180,394	69,635	611,984	592,792	621,865
INCOME TAXES (Note 4)									245,841	237,360	245,095
Net income									469,207	447,320	458,861
NET INCOME ATTRIBUTABLE TO COMMON SHAREHOLDERS	$ 43,857	$ 261,187	$ 125,362	$ 19,868	$ 15,738	$ 251,047	$ 134,916	$ 19,518	$ 450,274	$ 421,219	$ 424,969