Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	1 Months Ended			9 Months Ended
	Feb. 28, 2011	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2012 ARIZONA PUBLIC SERVICE COMPANY	Dec. 31, 2011 ARIZONA PUBLIC SERVICE COMPANY
Income Taxes
Long-term income tax receivables		$ 69,953	$ 68,633	$ 70,348	$ 69,028
Period over which the cash refunds are not expected to be received				12 months
Phase-in period of corporate income tax rate reductions beginning in 2014	4 years