Income Taxes - Summary of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax [Line Items]
Tax positions, that if recognized, would decrease our effective tax rate	$ 9,523	$ 11,207	$ 9,827
Unrecognized tax benefit interest expense/(benefit) recognized	(161)	752	(3,716)
Unrecognized tax benefit interest accrued	804	965	213
ARIZONA PUBLIC SERVICE COMPANY
Income Tax [Line Items]
Tax positions, that if recognized, would decrease our effective tax rate	9,523	11,207	9,827
Unrecognized tax benefit interest expense/(benefit) recognized	(161)	752	(3,716)
Unrecognized tax benefit interest accrued	$ 804	$ 965	$ 213