Selected Quarterly Financial Data (Unaudited) (APSC) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Consolidated quarterly financial information
Operating revenues	$ 667,892	$ 1,124,841	$ 799,799	$ 648,847					$ 3,241,379	$ 3,189,199	$ 3,153,656
Operations and maintenance	228,632	210,035	210,590	255,029					904,286	870,185	822,300
Operating income	78,715	435,017	196,992	35,784					746,508	714,883	616,128
Net income (loss) attributable to common shareholders	12,564	255,359	86,685	(15,135)					339,473	350,053	68,330
ARIZONA PUBLIC SERVICE COMPANY
Consolidated quarterly financial information
Operating revenues	666,504	1,124,057	798,686	647,994	653,644	1,116,220	799,467	611,476	3,237,241	3,180,807
Operations and maintenance	226,746	207,967	208,597	252,607	228,477	217,044	211,310	203,881	895,917	860,712	812,903
Operating income	70,626	292,783	145,400	45,574	60,344	277,009	146,249	65,435	554,383	549,037	469,799
Net income (loss) attributable to common shareholders	$ 14,292	$ 246,333	$ 87,705	$ (12,081)	$ 7,811	$ 226,648	$ 90,220	$ 10,984	$ 336,249	$ 335,663	$ 251,225