Long-Term Debt and Liquidity Matters (Details) (USD $)				1 Months Ended										1 Months Ended
	Jun. 30, 2011	Dec. 31, 2010	Feb. 23, 2011 Pinnacle West	Jul. 31, 2011 Pinnacle West Term loan facility	Feb. 28, 2011 Pinnacle West 5.91% Senior Notes	Feb. 23, 2011 Pinnacle West 5.91% Senior Notes	Jun. 30, 2011 Pinnacle West Credit facility maturing in 2013	Jun. 30, 2011 ARIZONA PUBLIC SERVICE COMPANY	Dec. 31, 2010 ARIZONA PUBLIC SERVICE COMPANY	Jun. 30, 2011 ARIZONA PUBLIC SERVICE COMPANY Line of credit facilities	Jun. 30, 2011 ARIZONA PUBLIC SERVICE COMPANY Credit facility maturing in 2013	Jun. 30, 2011 ARIZONA PUBLIC SERVICE COMPANY New Revolving credit facility maturing in 2015	Feb. 14, 2011 ARIZONA PUBLIC SERVICE COMPANY New Revolving credit facility maturing in 2015	Feb. 28, 2011 ARIZONA PUBLIC SERVICE COMPANY Revolving credit facility maturing in 2011	Jun. 30, 2011 ARIZONA PUBLIC SERVICE COMPANY ACC	Jun. 30, 2011 Line of credit facilities
Long-Term Debt and Liquidity Matters
Term loan facility			$ 175,000,000
Interest rate (as a percent)						5.91%
Repayment of debt				25,000,000	175,000,000
Current borrowing capacity on credit facility							200,000,000			1,000,000,000	500,000,000	500,000,000
Refinanced credit facility														489,000,000
Maximum commercial paper support available under credit facility							200,000,000			250,000,000
Maximum borrowing capacity on credit facility upon satisfaction of certain conditions and consent of lenders							300,000,000					700,000,000
Commercial paper borrowings							7,000,000
Number of line of credit facilities																2
Letter of credit													20,000,000
Debt Provisions
Required minimum common equity ratio ordered by ACC (as a percent)															40.00%
Total shareholder equity	3,613,705,000	3,683,327,000						3,746,067,000	3,824,953,000						3,700,000,000
Total capitalization															7,100,000,000
Dividend restrictions, minimum total shareholder equity required															$ 2,800,000,000