SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF REGISTRANT - Consolidated Statements of Cash Flows (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash Flows from Operating Activities
Net Income	$ 423,696,000	$ 439,966,000	$ 413,164,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	496,487,000	492,322,000	481,262,000
Deferred income taxes	159,023,000	249,296,000	187,023,000
Accounts receivable	(52,672,000)	(44,991,000)	14,587,000
Accounts payable	(353,000)	45,414,000	(96,600,000)
Net cash flow provided by operating activities	1,099,627,000	1,153,307,000	1,171,122,000
Cash flows from investing activities
Net cash flow used for investing activities	(922,668,000)	(1,009,401,000)	(872,994,000)
Cash flows from financing activities
Issuance of long-term debt	731,126,000	136,307,000	476,081,000
Dividends paid on common stock	(246,671,000)	(235,244,000)	(225,075,000)
Repayment of long-term debt	(652,578,000)	(122,828,000)	(654,286,000)
Common stock equity issuance	15,288,000	17,319,000	15,955,000
Other	161,000	299,000	170,000
Net cash flow used for financing activities	(178,881,000)	(160,582,000)	(305,509,000)
NET DECREASE IN CASH AND CASH EQUIVALENTS	(1,922,000)	(16,676,000)	(7,381,000)
CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR	9,526,000	26,202,000	33,583,000
CASH AND CASH EQUIVALENTS AT END OF YEAR	7,604,000	9,526,000	26,202,000
Pinnacle West
Cash Flows from Operating Activities
Net Income	397,595,000	406,074,000	381,542,000
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in earnings of subsidiaries - net	(411,528,000)	(420,926,000)	(391,528,000)
Depreciation and amortization	94,000	95,000	94,000
Deferred income taxes	4,406,000	(28,806,000)	(15,135,000)
Accounts receivable	(22,945,000)	21,671,000	28,763,000
Accounts payable	2,017,000	(2,449,000)	879,000
Accrued taxes and income tax receivable - net	(1,795,000)	1,402,000	(3,103,000)
Dividends received from subsidiaries	253,600,000	242,100,000	222,200,000
Other	18,432,000	(15,065,000)	(4,589,000)
Net cash flow provided by operating activities	239,876,000	204,096,000	219,123,000
Cash flows from investing activities
Investments in subsidiaries	(10,236,000)	(3,400,000)	0
Repayments of loans from subsidiaries	322,000	2,149,000	996,000
Advances of loans to subsidiaries	(1,450,000)	(2,099,000)	(1,200,000)
Net cash flow used for investing activities	(11,364,000)	(3,350,000)	(204,000)
Cash flows from financing activities
Issuance of long-term debt	125,000,000	0	125,000,000
Dividends paid on common stock	(246,671,000)	(235,244,000)	(225,075,000)
Repayment of long-term debt	(125,000,000)	0	(125,000,000)
Common stock equity issuance	15,288,000	17,319,000	15,955,000
Other	161,000	298,000	170,000
Net cash flow used for financing activities	(231,222,000)	(217,627,000)	(208,950,000)
NET DECREASE IN CASH AND CASH EQUIVALENTS	(2,710,000)	(16,881,000)	9,969,000
CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR	5,798,000	22,679,000	12,710,000
CASH AND CASH EQUIVALENTS AT END OF YEAR	$ 3,088,000	$ 5,798,000	$ 22,679,000