Income Taxes (Details) (USD $)	3 Months Ended	6 Months Ended
	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012
Income Taxes
Long-term income tax receivables		$ 71,274,000	$ 70,389,000
Income Tax Receivables		2,317,000	2,423,000
Income tax receivable that will be reclassified from long term to short-term	71,274,000
Decrease in uncertain tax positions lower bound		65,000,000
Decrease in uncertain tax positions upper bound		75,000,000
Income Taxes, additional disclosures
Percentage of bonus depreciation for federal income tax purposes		50.00%
Federal general business income tax credit carryforwards whose realization will be delayed on recognition of cash benefit			78,000,000
Federal general business income tax credit carryforwards reclassified to long-term deferred income taxes		39,000,000
Palo Verde VIE
Income Taxes
Income tax expense associates with the VIE's		0
ARIZONA PUBLIC SERVICE COMPANY
Income Taxes
Long-term income tax receivables		71,669,000	70,784,000
Income tax receivable that will be reclassified from long term to short-term	71,669,000
Decrease in uncertain tax positions lower bound		65,000,000
Decrease in uncertain tax positions upper bound		$ 75,000,000