CONSOLIDATED STATEMENTS OF CASH FLOWS $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 530,540	$ 507,949	$ 461,527
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization including nuclear fuel	650,955	610,629	565,011
Deferred fuel and purchased power	(78,277)	(48,405)	(60,303)
Deferred fuel and purchased power amortization	116,750	(14,767)	38,152
Allowance for equity funds used during construction	(52,319)	(47,011)	(42,140)
Deferred income taxes	117,355	248,164	206,870
Deferred investment tax credit	(5,170)	(4,587)	23,082
Change in derivative instruments fair value	0	(373)	(403)
Stock compensation	19,547	20,502	18,883
Changes in current assets and liabilities:
Customer and other receivables	37,530	(93,797)	(2,489)
Accrued unbilled revenues	(24,736)	(4,485)	(11,709)
Materials, supplies and fossil fuel	(6,103)	(6,683)	(1,491)
Income tax receivable	0	3,751	(3,162)
Other current assets	33,844	(10,580)	(23,324)
Accounts payable	(14,602)	(23,769)	(66,917)
Accrued taxes	6,597	9,982	447
Other current liabilities	28,174	19,154	29,594
Change in margin and collateral accounts — assets	143	(300)	673
Change in margin and collateral accounts — liabilities	(2,211)	(533)	17,735
Change in unrecognized tax benefits	(1,235)	5,891	1,628
Change in long-term regulatory liabilities	(109,284)	45,764	14,682
Change in other long-term assets	78,604	(68,480)	(60,163)
Change in other long-term liabilities	(48,958)	(29,980)	(82,793)
Net cash flow provided by operating activities	1,277,144	1,118,036	1,023,390
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(1,178,169)	(1,408,774)	(1,275,472)
Contributions in aid of construction	27,716	23,708	64,296
Allowance for borrowed funds used during construction	(25,180)	(22,112)	(19,970)
Proceeds from nuclear decommissioning trust sales and other special use funds	653,033	542,246	633,410
Investment in nuclear decommissioning trust and other special use funds	(672,165)	(544,527)	(635,691)
Other	1,941	(19,078)	(18,651)
Net cash flow used for investing activities	(1,192,824)	(1,428,537)	(1,252,078)
CASH FLOWS FROM FINANCING ACTIVITIES
Issuance of long-term debt	445,245	848,239	693,151
Repayment of long-term debt	(182,000)	(125,000)	(370,430)
Short-term borrowings and (repayments) — net	(7,000)	(107,800)	137,200
Short-term debt borrowings under revolving credit facility	45,000	58,000	40,000
Short-term debt repayments under revolving credit facility	(57,000)	(32,000)	0
Dividends paid on common stock	(308,892)	(289,793)	(274,229)
Common stock equity issuance and purchases - net	(5,055)	(13,390)	(4,867)
Distributions to noncontrolling interests	(22,744)	(22,744)	(22,744)
Net cash flow (used for) provided by financing activities	(92,446)	315,512	198,081
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	(8,126)	5,011	(30,607)
CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR	13,892	8,881	39,488
CASH AND CASH EQUIVALENTS AT END OF YEAR	5,766	13,892	8,881
Supplemental disclosure of cash flow information:
Income taxes, net of refunds	21,173	2,186	9,956
Interest, net of amounts capitalized	208,479	189,288	184,462
Significant non-cash investing and financing activities:
Accrued capital expenditures	132,620	130,404	114,855
Dividends declared but not paid	82,675	77,667	72,926
ARIZONA PUBLIC SERVICE COMPANY
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	589,758	523,802	481,634
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization including nuclear fuel	649,295	608,935	564,091
Deferred fuel and purchased power	(78,277)	(48,405)	(60,303)
Deferred fuel and purchased power amortization	116,750	(14,767)	38,152
Allowance for equity funds used during construction	(52,319)	(47,011)	(42,140)
Deferred income taxes	59,927	249,465	221,167
Deferred investment tax credit	(5,170)	(4,587)	23,082
Change in derivative instruments fair value	0	(373)	(403)
Changes in current assets and liabilities:
Customer and other receivables	35,406	(68,040)	(1,601)
Accrued unbilled revenues	(24,736)	(4,485)	(11,709)
Materials, supplies and fossil fuel	(6,206)	(6,503)	(1,454)
Income tax receivable	0	11,174	(14,567)
Other current assets	31,707	(6,775)	(21,640)
Accounts payable	(15,608)	(26,561)	(67,543)
Accrued taxes	19,008	26,773	(13,912)
Other current liabilities	25,070	27,912	5,097
Change in margin and collateral accounts — assets	143	(300)	673
Change in margin and collateral accounts — liabilities	(2,211)	(533)	17,735
Change in unrecognized tax benefits	(1,235)	5,891	1,628
Change in long-term regulatory liabilities	(109,284)	45,764	14,682
Change in other long-term assets	77,952	(78,540)	(45,866)
Change in other long-term liabilities	(55,169)	(31,106)	(76,855)
Net cash flow provided by operating activities	1,254,801	1,161,730	1,009,948
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(1,169,061)	(1,381,930)	(1,248,010)
Contributions in aid of construction	27,716	23,708	64,296
Allowance for borrowed funds used during construction	(25,180)	(22,112)	(19,481)
Proceeds from nuclear decommissioning trust sales and other special use funds	653,033	542,246	633,410
Investment in nuclear decommissioning trust and other special use funds	(672,165)	(544,527)	(635,691)
Other	(1,789)	(18,538)	(13,865)
Net cash flow used for investing activities	(1,187,446)	(1,401,153)	(1,219,341)
CASH FLOWS FROM FINANCING ACTIVITIES
Issuance of long-term debt	295,245	549,478	693,151
Repayment of long-term debt	(182,000)	0	(370,430)
Short-term borrowings and (repayments) — net	0	(135,500)	135,500
Short-term debt borrowings under revolving credit facility	25,000	0	0
Short-term debt repayments under revolving credit facility	(25,000)	0	0
Dividends paid on common stock	(316,000)	(296,800)	(281,300)
Equity infusion from Pinnacle West	150,000	150,000	42,000
Distributions to noncontrolling interests	(22,744)	(22,744)	(22,744)
Net cash flow (used for) provided by financing activities	(75,499)	244,434	196,177
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	(8,144)	5,011	(13,216)
CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR	13,851	8,840	22,056
CASH AND CASH EQUIVALENTS AT END OF YEAR	5,707	13,851	8,840
Supplemental disclosure of cash flow information:
Income taxes, net of refunds	77,942	(14,098)	26,864
Interest, net of amounts capitalized	196,419	184,210	181,809
Significant non-cash investing and financing activities:
Accrued capital expenditures	132,620	130,057	114,874
Dividends declared but not paid	$ 82,700	$ 77,700	$ 72,900