Long-Term Debt and Liquidity Matters Narrative (Details) (USD $)	9 Months Ended								9 Months Ended			9 Months Ended																								0 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	May 09, 2014 Pinnacle West Revolving Credit Facility Revolving credit facility maturing in 2016	Sep. 30, 2014 Pinnacle West Line of Credit New revolving credit facility maturing in 2019	May 09, 2014 Pinnacle West Line of Credit New revolving credit facility maturing in 2019	Sep. 30, 2014 Pinnacle West Commercial Paper New revolving credit facility maturing in 2019	Sep. 30, 2014 Pinnacle West Letter of Credit New revolving credit facility maturing in 2019	Sep. 30, 2014 APS	Sep. 30, 2013 APS	Dec. 31, 2013 APS	Sep. 30, 2014 APS SCE Four Corners Units 4 and 5 Series	Dec. 30, 2013 APS SCE Four Corners Units 4 and 5	Sep. 30, 2014 APS ACC	Sep. 30, 2014 APS ACC Minimum	May 09, 2014 APS Revolving Credit Facility Revolving credit facility maturing in 2016	Sep. 30, 2014 APS Line of Credit Facility	Sep. 30, 2014 APS Line of Credit Revolving credit facility maturing in 2018	Sep. 30, 2014 APS Line of Credit New revolving credit facility maturing in 2019	May 09, 2014 APS Line of Credit New revolving credit facility maturing in 2019	Sep. 30, 2014 APS Commercial Paper	Sep. 30, 2014 APS Letter of Credit	Jul. 12, 2013 APS Bond Pollution Control Revenue Refunding Bonds, 1994 Series A	Oct. 11, 2013 APS Bond Pollution Control Revenue Refunding Bonds, 1994 Series C	May 01, 2014 APS Bond Pollution Control Revenue Refunding Bonds, 2009 Series A, D and E	May 14, 2014 APS Bond 2009 series A bonds	May 01, 2014 APS Bond 2009 series D and series E bonds	Sep. 23, 2014 APS Bond Pollution Control Revenue Refunding Bonds, 2009 Series A	Jun. 01, 2014 APS Bond Pollution Control Revenue Refunding Bonds, 2009 Series A	May 30, 2014 APS Bond Pollution Control Revenue Refunding Bonds, 2009 Series A	Jun. 01, 2014 APS Bond 2009 series B and series C bonds	Oct. 01, 2014 APS Bond Series C Bonds 2009	Sep. 30, 2014 APS Bond Series B Bonds 2009	Jan. 10, 2014 APS Senior Notes 4.70% unsecured senior notes that mature on January 15, 2044	Jun. 18, 2014 APS Senior Notes 3.35% unsecured senior note	Jun. 18, 2014 APS Senior Notes 5.80% senior notes	Jun. 18, 2014 APS Senior Notes 5.80% senior notes
Long-Term Debt and Liquidity Matters
Current borrowing capacity on credit facility				$ 200,000,000		$ 200,000,000										$ 500,000,000	$ 1,000,000,000	$ 500,000,000	$ 500,000,000	$ 500,000,000
Maximum commercial paper support available under credit facility							200,000,000														250,000,000
Commercial Paper							0														19,000,000
Maximum borrowing capacity on credit facility upon satisfaction of certain conditions and consent of lenders					300,000,000													700,000,000
Outstanding borrowings					0												0
Outstanding letters of credit								0														76,000,000
Debt instrument repurchased face amount																							33,000,000	32,000,000	100,000,000					38,000,000	64,000,000
Debt issued																										36,000,000		38,000,000	13,000,000			32,000,000		250,000,000	250,000,000
Interest rate (as a percent)																																		4.70%	3.35%		5.80%
Ownership interest acquired												48.00%	48.00%
Number of tax-exempt indebtedness series re-acquired												2
Debt expected to be issued in the next 12 months																											64,000,000						32,000,000
Repayment of long-term debt	503,583,000	72,777,000							503,583,000	72,777,000																										300,000,000
Number of line of credit facilities																	2
Debt Provisions
Required common equity ratio ordered by ACC (as a percent)															40.00%
Total shareholder equity	4,491,916,000		4,194,470,000						4,599,624,000		4,308,884,000			4,600,000,000
Total capitalization														8,100,000,000
Dividend restrictions, shareholder equity required														$ 3,200,000,000