Regulatory Matters Regulatory Matters - Deferred Fuel and Purchased Power Regulatory Asset (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Change in regulatory asset
Deferred fuel and purchased power	$ (26,927,000)	$ 21,678,000	$ 71,573,000
Deferred fuel and purchased power amortization	40,757,000	31,190,000	(116,716,000)
ARIZONA PUBLIC SERVICE COMPANY
Change in regulatory asset
Deferred fuel and purchased power	(26,927,000)	21,678,000	71,573,000
Deferred fuel and purchased power amortization	40,757,000	31,190,000	(116,716,000)
ACC | ARIZONA PUBLIC SERVICE COMPANY | Power Supply Adjustor (PSA) | Cost Recovery Mechanisms
Change in regulatory asset
Beginning balance	21,000,000	73,000,000
Deferred fuel and purchased power	27,000,000	(21,000,000)
Deferred fuel and purchased power amortization	(41,000,000)	(31,000,000)
Ending balance	$ 7,000,000	$ 21,000,000