CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
CURRENT ASSETS
Cash and cash equivalents	$ 5,766	$ 13,892
Customer and other receivables	267,887	305,147
Accrued unbilled revenues	137,170	112,434
Allowance for doubtful accounts	(4,069)	(2,513)
Materials and supplies (at average cost)	269,065	264,012
Fossil fuel (at average cost)	25,029	25,258
Assets from risk management activities (Note 16)	1,113	1,931
Deferred fuel and purchased power regulatory asset (Note 3)	37,164	75,637
Other regulatory assets (Note 3)	129,738	172,451
Other current assets	56,128	48,039
Total current assets	924,991	1,016,288
INVESTMENTS AND OTHER ASSETS
Nuclear decommissioning trust (Notes 13 and 19)	851,134	871,000
Other special use funds (Notes 13 and 19)	236,101	32,542
Other assets	103,247	52,040
Total investments and other assets	1,190,482	955,582
PROPERTY, PLANT AND EQUIPMENT (Notes 1, 6 and 9)
Plant in service and held for future use	18,736,628	17,798,061
Accumulated depreciation and amortization	(6,366,014)	(6,128,535)
Net	12,370,614	11,669,526
Construction work in progress	1,170,062	1,291,498
Palo Verde sale leaseback, net of accumulated depreciation of $245,275 and $241,405 (Note 18)	105,775	109,645
Intangible assets, net of accumulated amortization	262,902	257,189
Nuclear fuel, net of accumulated amortization of $137,850 and $144,070	120,217	117,408
Total property, plant and equipment	14,029,570	13,445,266
DEFERRED DEBITS
Regulatory assets (Notes 1, 3 and 4)	1,342,941	1,202,302
Assets for other postretirement benefits (Note 7)	46,906	268,978
Other	129,312	130,666
Total deferred debits	1,519,159	1,601,946
Total Assets	17,664,202	17,019,082
CURRENT LIABILITIES
Accounts payable	277,336	256,442
Accrued taxes	154,819	148,946
Accrued interest	61,107	56,397
Common dividends payable	82,675	77,667
Short-term borrowings (Note 5)	76,400	95,400
Customer deposits	91,174	70,388
Current maturities of long-term debt (Note 6)	500,000	82,000
Liabilities from risk management activities (Note 16)	35,506	59,252
Liabilities for asset retirements (Note 11)	19,842	4,745
Regulatory liabilities (Note 3)	165,876	100,086
Other current liabilities	184,229	246,529
Total current liabilities	1,648,964	1,197,852
LONG-TERM DEBT LESS CURRENT MATURITIES (Note 6)	4,638,232	4,789,713
DEFERRED CREDITS AND OTHER
Deferred income taxes (Note 4)	1,807,421	1,690,805
Regulatory liabilities (Notes 1, 3, 4 and 7)	2,325,976	2,452,536
Liabilities for asset retirements (Note 11)	706,703	674,784
Liabilities for pension benefits (Note 7)	443,170	327,300
Liabilities from risk management activities (Note 16)	24,531	37,170
Customer advances	137,153	113,996
Coal mine reclamation	212,785	231,597
Deferred investment tax credit	200,405	205,575
Unrecognized tax benefits (Note 4)	22,517	13,115
Other	147,640	148,909
Total deferred credits and other	6,028,301	5,895,787
COMMITMENTS AND CONTINGENCIES (SEE NOTES)
EQUITY
Common stock, no par value; authorized 150,000,000 shares, 112,159,896 and 111,816,170 issued at respective dates	2,634,265	2,614,805
Treasury stock at cost; 58,135 shares at end of 2018 and 64,463 shares at end of 2017	(4,825)	(5,624)
Total common stock	2,629,440	2,609,181
Retained earnings	2,641,183	2,442,511
Accumulated other comprehensive loss	(47,708)	(45,002)
Total shareholders’ equity	5,222,915	5,006,690
Noncontrolling interests (Note 18)	125,790	129,040
Total equity	5,348,705	5,135,730
Total Liabilities and Equity	17,664,202	17,019,082
ARIZONA PUBLIC SERVICE COMPANY
CURRENT ASSETS
Cash and cash equivalents	5,707	13,851
Customer and other receivables	257,654	292,791
Accrued unbilled revenues	137,170	112,434
Allowance for doubtful accounts	(4,069)	(2,513)
Materials and supplies (at average cost)	269,065	262,630
Fossil fuel (at average cost)	25,029	25,258
Assets from risk management activities (Note 16)	1,113	1,931
Deferred fuel and purchased power regulatory asset (Note 3)	37,164	75,637
Other regulatory assets (Note 3)	129,738	172,451
Other current assets	35,111	41,055
Total current assets	893,682	995,525
INVESTMENTS AND OTHER ASSETS
Nuclear decommissioning trust (Notes 13 and 19)	851,134	871,000
Other special use funds (Notes 13 and 19)	236,101	30,358
Other assets	40,817	36,796
Total investments and other assets	1,128,052	938,154
PROPERTY, PLANT AND EQUIPMENT (Notes 1, 6 and 9)
Plant in service and held for future use	18,733,142	17,654,078
Accumulated depreciation and amortization	(6,362,771)	(6,041,965)
Net	12,370,371	11,612,113
Construction work in progress	1,170,062	1,266,636
Palo Verde sale leaseback, net of accumulated depreciation of $245,275 and $241,405 (Note 18)	105,775	109,645
Intangible assets, net of accumulated amortization	262,746	257,028
Nuclear fuel, net of accumulated amortization of $137,850 and $144,070	120,217	117,408
Total property, plant and equipment	14,029,171	13,362,830
DEFERRED DEBITS
Regulatory assets (Notes 1, 3 and 4)	1,342,941	1,202,302
Assets for other postretirement benefits (Note 7)	43,212	265,139
Other	128,265	129,801
Total deferred debits	1,514,418	1,597,242
Total Assets	17,565,323	16,893,751
CURRENT LIABILITIES
Accounts payable	266,277	247,852
Accrued taxes	176,357	157,349
Accrued interest	60,228	55,533
Common dividends payable	82,700	77,700
Customer deposits	91,174	70,388
Current maturities of long-term debt (Note 6)	500,000	82,000
Liabilities from risk management activities (Note 16)	35,506	59,252
Liabilities for asset retirements (Note 11)	19,842	4,192
Regulatory liabilities (Note 3)	165,876	100,086
Other current liabilities	178,137	243,922
Total current liabilities	1,576,097	1,098,274
DEFERRED CREDITS AND OTHER
Deferred income taxes (Note 4)	1,812,664	1,742,485
Regulatory liabilities (Notes 1, 3, 4 and 7)	2,325,976	2,452,536
Liabilities for asset retirements (Note 11)	706,703	666,527
Liabilities for pension benefits (Note 7)	425,404	306,542
Liabilities from risk management activities (Note 16)	24,531	37,170
Customer advances	137,153	113,996
Coal mine reclamation	212,785	215,830
Deferred investment tax credit	200,405	205,575
Unrecognized tax benefits (Note 4)	41,861	43,876
Other	125,511	133,779
Total deferred credits and other	6,012,993	5,918,316
COMMITMENTS AND CONTINGENCIES (SEE NOTES)
EQUITY
Total common stock	178,162	178,162
Additional paid-in capital	2,721,696	2,571,696
Retained earnings	2,788,256	2,533,954
Accumulated other comprehensive loss	(27,107)	(26,983)
Total shareholders’ equity	5,661,007	5,256,829
Noncontrolling interests (Note 18)	125,790	129,040
Total equity	5,786,797	5,385,869
Long-term debt less current maturities (Note 6)	4,189,436	4,491,292
Total capitalization	9,976,233	9,877,161
Total Liabilities and Equity	$ 17,565,323	$ 16,893,751