Palo Verde Sale Leaseback Variable Interest Entities Narrative (Details) (USD $)	3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended		0 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014 Arizona Public Service Company item	Sep. 30, 2013 Arizona Public Service Company	Sep. 30, 2014 Arizona Public Service Company item	Sep. 30, 2013 Arizona Public Service Company	Dec. 31, 1986 Arizona Public Service Company Trust	Sep. 30, 2014 Arizona Public Service Company Consolidation of VIEs	Sep. 30, 2013 Arizona Public Service Company Consolidation of VIEs	Sep. 30, 2014 Arizona Public Service Company Consolidation of VIEs	Sep. 30, 2013 Arizona Public Service Company Consolidation of VIEs	Jul. 07, 2014 Arizona Public Service Company Consolidation of VIEs Through 2023 Lease	Jul. 07, 2014 Arizona Public Service Company Consolidation of VIEs Through 2033 Lease	Jul. 07, 2014 Arizona Public Service Company Consolidation of VIEs Period 2016 through 2023	Jul. 07, 2014 Arizona Public Service Company Consolidation of VIEs Period 2024 through 2033	Jul. 07, 2014 Maximum Arizona Public Service Company Consolidation of VIEs Period 2024 through 2033
Palo Verde Sale Leaseback Variable Interest Entities
Number of VIE lessor trusts					3		3		3
Annual lease payments							$ 49,000,000									$ 23,000,000	$ 16,000,000
Number of leases under which assets are retained														1	2
Lease period																		2 years
Increase in net income due to consolidation of Palo Verde Sale Leaseback Trusts	4,125,000	8,555,000	21,976,000	25,338,000	4,125,000	8,555,000	21,976,000	25,338,000		4,000,000	9,000,000	22,000,000	25,000,000
Maximum payment to the VIEs' noncontrolling equity participants upon the occurrence of certain unlikely events												138,000,000
VIE debt to be assumed upon the occurrence of certain unlikely events												$ 38,000,000