Common Stock and Treasury Stock (Details) (USD $)				1 Months Ended							12 Months Ended							12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Apr. 30, 2010 Pinnacle West	Dec. 31, 2012 Pinnacle West	Dec. 31, 2011 Pinnacle West	Apr. 10, 2010 Pinnacle West	Dec. 31, 2012 ARIZONA PUBLIC SERVICE COMPANY	Dec. 31, 2011 ARIZONA PUBLIC SERVICE COMPANY	Dec. 31, 2010 ARIZONA PUBLIC SERVICE COMPANY	Dec. 31, 2012 Common Stock	Dec. 31, 2011 Common Stock	Dec. 31, 2010 Common Stock	Dec. 31, 2012 Common Stock ARIZONA PUBLIC SERVICE COMPANY	Dec. 31, 2011 Common Stock ARIZONA PUBLIC SERVICE COMPANY	Dec. 31, 2010 Common Stock ARIZONA PUBLIC SERVICE COMPANY	Dec. 31, 2009 Common Stock ARIZONA PUBLIC SERVICE COMPANY	Dec. 31, 2012 Treasury Stock	Dec. 31, 2011 Treasury Stock	Dec. 31, 2010 Treasury Stock	Dec. 31, 2012 Serial preferred stock Pinnacle West
Changes in equity
Balance	$ 4,102,289,000	$ 3,930,586,000	$ 3,775,226,000		$ 4,102,290,000	$ 3,930,586,000		$ 4,222,483,000	$ 4,051,406,000	$ 3,916,037,000	$ 2,444,247,000	$ 2,421,372,000	$ 2,153,295,000	$ 178,162,000	$ 178,162,000	$ 178,162,000	$ 178,162,000	$ (4,717,000)	$ (2,239,000)	$ (3,812,000)
Balance at the beginning of the period (in shares)	109,837,957	109,356,974									109,356,974	108,820,067	101,527,937					(111,161)	(50,410)	(93,239)
Common stock issuance											22,676,000	22,875,000	268,077,000
Common stock issuance (in shares)				6,900,000							480,983	536,907	7,292,130
Purchase of treasury stock																		(4,607,000)	(3,720,000)	(82,000)
Purchase of treasury stock (in shares)																		(89,629)	(88,440)	(1,994)
Reissuance of treasury stock for stock compensation																		5,113,000	1,242,000	1,655,000
Reissuance of treasury stock for stock compensation (in shares)																		105,598	27,689	44,823
Balance	4,102,289,000	3,930,586,000	3,775,226,000		4,102,290,000	3,930,586,000		4,222,483,000	4,051,406,000	3,916,037,000	2,466,923,000	2,444,247,000	2,421,372,000	178,162,000	178,162,000	178,162,000	178,162,000	(4,211,000)	(4,717,000)	(2,239,000)
Balance at the end of the period (in shares)	109,837,957	109,356,974									109,837,957	109,356,974	108,820,067					(95,192)	(111,161)	(50,410)
Offering price of common stock issued (in dollars per share)							$ 38.00
Net proceeds from issuance of common stock				$ 253,000,000
Serial preferred stock authorized								15,535,000													10,000,000
Par value of type 1 preferred stock authorized (in dollars per share)								$ 25
Par value of type 2 preferred stock authorized (in dollars per share)								$ 50
Par value of type 3 preferred stock authorized (in dollars per share)								$ 100