Selected Quarterly Financial Data (Unaudited) (Details) (USD $) In Thousands, except Per Share data, 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
Selected Quarterly Financial Information [Line Items]
OPERATING REVENUES	$ 726,450us-gaap_SalesRevenueNet	$ 1,172,667us-gaap_SalesRevenueNet	$ 906,264us-gaap_SalesRevenueNet	$ 686,251us-gaap_SalesRevenueNet	$ 699,762us-gaap_SalesRevenueNet	$ 1,152,392us-gaap_SalesRevenueNet	$ 915,822us-gaap_SalesRevenueNet	$ 686,652us-gaap_SalesRevenueNet	$ 3,491,632us-gaap_SalesRevenueNet	$ 3,454,628us-gaap_SalesRevenueNet	$ 3,301,804us-gaap_SalesRevenueNet
Operations and maintenance	260,503	223,418	211,222	212,882	238,854	233,323	229,300	223,250	908,025	924,727	884,769
Operating income	60,184us-gaap_OperatingIncomeLoss	421,775us-gaap_OperatingIncomeLoss	254,113us-gaap_OperatingIncomeLoss	75,170us-gaap_OperatingIncomeLoss	83,900us-gaap_OperatingIncomeLoss	415,688us-gaap_OperatingIncomeLoss	259,812us-gaap_OperatingIncomeLoss	86,923us-gaap_OperatingIncomeLoss	811,242us-gaap_OperatingIncomeLoss	846,323us-gaap_OperatingIncomeLoss	851,755us-gaap_OperatingIncomeLoss
Income taxes	5,007us-gaap_IncomeTaxExpenseBenefit	134,753us-gaap_IncomeTaxExpenseBenefit	74,540us-gaap_IncomeTaxExpenseBenefit	6,405us-gaap_IncomeTaxExpenseBenefit	9,167us-gaap_IncomeTaxExpenseBenefit	131,912us-gaap_IncomeTaxExpenseBenefit	77,043us-gaap_IncomeTaxExpenseBenefit	12,469us-gaap_IncomeTaxExpenseBenefit	220,705us-gaap_IncomeTaxExpenseBenefit	230,591us-gaap_IncomeTaxExpenseBenefit	237,317us-gaap_IncomeTaxExpenseBenefit
Income from continuing operations	9,535	248,086	141,384	24,691	32,814	234,718	139,598	32,836	423,696	439,966	418,993
Net income attributable to common shareholders	5,410	243,961	132,458	15,766	24,260	226,163	131,207	24,444	397,595	406,074	381,542
EARNINGS PER WEIGHTED-AVERAGE COMMON SHARE OUTSTANDING
Net income attributable to common shareholders - basic (in dollars per share)	$ 0.05us-gaap_EarningsPerShareBasic	$ 2.20us-gaap_EarningsPerShareBasic	$ 1.20us-gaap_EarningsPerShareBasic	$ 0.14us-gaap_EarningsPerShareBasic	$ 0.22us-gaap_EarningsPerShareBasic	$ 2.06us-gaap_EarningsPerShareBasic	$ 1.19us-gaap_EarningsPerShareBasic	$ 0.22us-gaap_EarningsPerShareBasic	$ 3.59us-gaap_EarningsPerShareBasic	$ 3.69us-gaap_EarningsPerShareBasic	$ 3.48us-gaap_EarningsPerShareBasic
Net income attributable to common shareholders — diluted (in dollars per share)	$ 0.05us-gaap_EarningsPerShareDiluted	$ 2.20us-gaap_EarningsPerShareDiluted	$ 1.19us-gaap_EarningsPerShareDiluted	$ 0.14us-gaap_EarningsPerShareDiluted	$ 0.22us-gaap_EarningsPerShareDiluted	$ 2.04us-gaap_EarningsPerShareDiluted	$ 1.18us-gaap_EarningsPerShareDiluted	$ 0.22us-gaap_EarningsPerShareDiluted	$ 3.58us-gaap_EarningsPerShareDiluted	$ 3.66us-gaap_EarningsPerShareDiluted	$ 3.45us-gaap_EarningsPerShareDiluted
ARIZONA PUBLIC SERVICE COMPANY
Selected Quarterly Financial Information [Line Items]
Electric domestic regulated revenue	725,633	1,172,190	905,578	685,545	698,824	1,151,535	915,065	685,827	3,488,946	3,451,251	3,293,489
Operations and maintenance	253,668	212,430	208,059	208,285	229,505	222,617	224,950	220,752	882,442	897,824	873,916
Operating income	54,835	287,928	180,394	69,635	79,024	284,251	183,728	74,862	592,792	621,865	605,529
Income taxes									237,360	245,095	244,396
Net income attributable to common shareholders	$ 15,738	$ 251,047	$ 134,916	$ 19,518	$ 30,024	$ 234,954	$ 133,949	$ 26,042	$ 421,219	$ 424,969	$ 395,497

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