Common Stock and Treasury Stock (Details) (USD $)	12 Months Ended		1 Months Ended				12 Months Ended			12 Months Ended							12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Apr. 30, 2010 Pinnacle West	Dec. 31, 2011 Pinnacle West	Dec. 31, 2010 Pinnacle West	Apr. 10, 2010 Pinnacle West	Dec. 31, 2009 ARIZONA PUBLIC SERVICE COMPANY	Dec. 31, 2011 ARIZONA PUBLIC SERVICE COMPANY	Dec. 31, 2010 ARIZONA PUBLIC SERVICE COMPANY	Dec. 31, 2011 Common Stock	Dec. 31, 2010 Common Stock	Dec. 31, 2009 Common Stock	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, 2008 Common Stock ARIZONA PUBLIC SERVICE COMPANY	Dec. 31, 2011 Treasury Stock	Dec. 31, 2010 Treasury Stock	Dec. 31, 2009 Treasury Stock	Dec. 31, 2011 Serial preferred stock Pinnacle West
Balance	$ 3,775,226,000	$ 3,428,004,000		$ 3,930,586,000	$ 3,775,226,000			$ 4,051,406,000	$ 3,916,037,000	$ 2,421,372,000	$ 2,153,295,000	$ 2,151,323,000	$ 178,162,000	$ 178,162,000	$ 178,162,000	$ 178,162,000	$ (2,239,000)	$ (3,812,000)	$ (2,854,000)
Balance at the beginning of the period (in shares)	108,820,067									108,820,067	101,527,937	100,948,436					(50,410)	(93,239)	(59,827)
Common stock issuance										11,057,000	263,297,000	10,620,000
Common stock issuance (in shares)	0	108,820,067	6,900,000							249,602	7,172,405	354,995
Purchase of treasury stock																	(3,720,000)	(82,000)	(2,156,000)
Purchase of treasury stock (in shares)																	(88,440)	(1,994)	(66,173)
Reissuance of treasury stock for stock compensation																	1,242,000	1,655,000	1,198,000
Reissuance of treasury stock for stock compensation (in shares)																	27,689	44,823	32,761
Other							9,074,000			11,818,000	4,780,000	(8,648,000)
Other (in shares)										287,305	119,725	224,506
Balance	3,930,586,000	3,775,226,000		3,930,586,000	3,775,226,000		3,527,679,000	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 end of the period (in shares)	109,356,974	108,820,067								109,356,974	108,820,067	101,527,937					(111,161)	(50,410)	(93,239)
Common stock issued (in shares)	0	108,820,067	6,900,000							249,602	7,172,405	354,995
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 preferred stock authorized (in dollars per share)							$ 100	$ 25	$ 50