SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF REGISTRANT - Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current assets
Cash and cash equivalents	$ 39,488	$ 7,604	$ 9,526	$ 26,202
Accounts receivable	274,691	297,740
Income tax receivable	589	3,098
Other current assets	37,242	38,817
Total current assets	890,516	973,435
Investments and other assets
Other assets	52,518	54,047
Total investments and other assets	799,820	785,533
Total Assets	15,028,258	14,288,890
Current liabilities
Accounts payable	297,480	295,211
Accrued taxes (Note 4)	138,600	140,613
Common dividends payable	69,363	65,790
Other current liabilities	197,861	178,962
Total current liabilities	1,442,317	1,559,143
Long-term debt less current maturities	3,462,391	3,006,573
Deferred credits and other
Deferred income taxes	2,723,425	2,582,636
Other	186,345	188,286
Total deferred credits and other	5,404,093	5,204,072
Common stock equity
Common stock	2,541,668	2,512,970
Accumulated other comprehensive loss	(44,748)	(68,141)	(78,053)
Retained earnings	2,092,803	1,926,065
Total shareholders’ equity	4,583,917	4,367,493
Noncontrolling interests	135,540	151,609
Total equity	4,719,457	4,519,102	4,340,460	4,102,289
Total Liabilities and Equity	15,028,258	14,288,890
Pinnacle West
Current assets
Cash and cash equivalents	17,432	3,088	$ 5,798	$ 22,679
Accounts receivable	93,093	99,958
Current deferred income taxes	0	66,979
Income tax receivable	14,895	7,329
Other current assets	197	124
Total current assets	125,617	177,478
Investments and other assets
Investments in subsidiaries	4,815,236	4,630,570
Deferred income taxes	41,065	0
Other assets	43,422	43,051
Total investments and other assets	4,899,723	4,673,621
Total Assets	5,025,340	4,851,099
Current liabilities
Accounts payable	5,901	5,250
Accrued taxes (Note 4)	6,904	12,220
Common dividends payable	69,363	65,790
Other current liabilities	33,120	38,992
Total current liabilities	115,288	122,252
Long-term debt less current maturities	125,000	125,000
Deferred credits and other
Deferred income taxes	0	12,055
Pension liabilities	21,933	29,228
Other	43,662	43,462
Total deferred credits and other	65,595	84,745
Common stock equity
Common stock	2,535,862	2,509,569
Accumulated other comprehensive loss	(44,748)	(68,141)
Retained earnings	2,092,803	1,926,065
Total shareholders’ equity	4,583,917	4,367,493
Noncontrolling interests	135,540	151,609
Total equity	4,719,457	4,519,102
Total Liabilities and Equity	$ 5,025,340	$ 4,851,099