SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF REGISTRANT - Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current assets
Cash and cash equivalents	$ 8,881	$ 39,488	$ 7,604	$ 9,526
Accounts receivable	250,491	274,691
Income tax receivable	3,751	589
Other current assets	45,028	37,242
Total current assets	822,219	890,516
Investments and other assets
Other assets	69,063	52,518
Total investments and other assets	848,650	799,820
Total Assets	16,004,253	15,028,258
Current liabilities
Accounts payable	264,631	297,480
Accrued taxes	138,964	138,600
Common dividends payable	72,926	69,363
Short-term borrowings	177,200	0
Current maturities of long-term debt	125,000	357,580
Other current liabilities	244,000	197,861
Total current liabilities	1,292,946	1,442,317
Deferred credits and other
Long-term debt less current maturities	4,021,785	3,462,391
Other	156,784	186,345
Total deferred credits and other	5,753,610	5,404,093
Common stock equity
Common stock	2,596,030	2,541,668
Accumulated other comprehensive loss	(43,822)	(44,748)
Retained earnings	2,255,547	2,092,803
Total shareholders’ equity	4,803,622	4,583,917
Noncontrolling interests	132,290	135,540
Total equity	4,935,912	4,719,457	4,519,102	4,340,460
Total Liabilities and Equity	16,004,253	15,028,258
Pinnacle West
Current assets
Cash and cash equivalents	41	17,432	$ 3,088	$ 5,798
Accounts receivable	81,751	93,093
Income tax receivable	0	14,895
Other current assets	340	197
Total current assets	82,132	125,617
Investments and other assets
Investments in subsidiaries	5,084,035	4,815,236
Deferred income taxes	53,805	41,065
Other assets	38,500	43,422
Total investments and other assets	5,176,340	4,899,723
Total Assets	5,258,472	5,025,340
Current liabilities
Accounts payable	5,421	5,901
Accrued taxes	12,050	6,904
Common dividends payable	72,926	69,363
Short-term borrowings	41,700	0
Current maturities of long-term debt	125,000	0
Other current liabilities	31,182	33,120
Total current liabilities	288,279	115,288
Deferred credits and other
Long-term debt less current maturities	0	125,000
Pension liabilities	21,057	21,933
Other	13,224	43,662
Total deferred credits and other	34,281	65,595
Common stock equity
Common stock	2,591,897	2,535,862
Accumulated other comprehensive loss	(43,822)	(44,748)
Retained earnings	2,255,547	2,092,803
Total shareholders’ equity	4,803,622	4,583,917
Noncontrolling interests	132,290	135,540
Total equity	4,935,912	4,719,457
Total Liabilities and Equity	$ 5,258,472	$ 5,025,340