CONSOLIDATED BALANCE SHEETS (APSC) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010	Sep. 30, 2009
PROPERTY, PLANT AND EQUIPMENT (Notes 1, 6, 9 and 10)
Plant in service and held for future use	$ 13,753,971	$ 13,201,960
Accumulated depreciation and amortization	(4,709,991)	(4,514,204)
Net	9,043,980	8,687,756
Construction work in progress	496,745	459,361
Palo Verde sale leaseback, net of accumulated depreciation of $218,186 and $213,094 (Note 20)	132,864	137,956
Intangible assets, net of accumulated amortization of $372,573 and $329,444	170,571	184,952
Nuclear fuel, net of accumulated amortization of $113,375 and $85,270	118,098	108,794
Total property, plant and equipment	9,962,258	9,578,819
INVESTMENTS AND OTHER ASSETS
Nuclear decommissioning trust (Notes 14 and 23)	513,733	469,886
Assets from risk management activities (Note 18)	49,322	39,032
Other assets	64,588	116,216
Total investments and other assets	627,643	625,134
CURRENT ASSETS
Cash and cash equivalents	33,583	110,188
Customer and other receivables	284,183	324,207
Accrued unbilled revenues	125,239	103,292
Allowance for doubtful accounts	(3,748)	(7,981)
Materials and supplies (at average cost)	204,387	181,414
Fossil fuel (at average cost)	22,000	21,575
Assets from risk management activities (Note 18)	30,264	73,788
Deferred fuel and purchased power regulatory asset (Note 3)	27,549
Other regulatory assets (Note 3)	69,072	62,286
Deferred income taxes (Notes 4 and S-1)	130,571	124,897
Other current assets	26,904	28,362
Total current assets	956,470	1,024,511
DEFERRED DEBITS
Regulatory assets (Notes 1, 3, 4 and S-1)	1,352,079	986,370
Income tax receivable (Note 4 and S-1)	68,633	65,103	69,000
Other	143,935	113,061
Total deferred debits	1,564,647	1,164,534
TOTAL ASSETS	13,111,018	12,392,998
CAPITALIZATION
Common stock	2,439,530	2,419,133
Retained earnings	1,534,483	1,423,961
Accumulated other comprehensive (loss):
Pension and other postretirement benefits (Note 8)	(65,447)	(59,420)
Derivative instruments	(86,716)	(100,347)
Total shareholder equity	3,821,850	3,683,327
Noncontrolling interests (Note 20)	108,736	91,899
Total equity	3,930,586	3,775,226
Long-term debt less current maturities (Note 6)	2,953,507	2,948,991
Palo Verde sale leaseback lessor notes less current maturities (Notes 6 and 20)	65,547	96,803
CURRENT LIABILITIES
Current maturities of long-term debt (Note 6)	477,435	631,879
Accounts payable	326,987	236,354
Accrued taxes	120,289	104,711
Accrued interest	54,872	54,831
Customer deposits	72,176	68,322
Liabilities from risk management activities (Note 18)	53,968	58,976
Deferred fuel and purchased power regulatory liability (Note 3)		58,442
Other regulatory liabilities (Note 3)	88,362	80,526
Other current liabilities	148,616	139,063
Total current liabilities	1,342,705	1,449,704
DEFERRED CREDITS AND OTHER
Deferred income taxes (Notes 4 and S-1)	1,925,388	1,863,861
Regulatory liabilities (Notes 1, 3, 4, and S-1)	737,332	614,063
Liability for asset retirements (Note 12)	279,643	328,571
Liabilities for pension and other postretirement benefits (Note 8)	1,268,910	813,121
Liabilities from risk management activities (Note 18)	82,495	65,390
Customer advances	116,805	121,645
Coal mine reclamation	117,896	117,243
Unrecognized tax benefits (Notes 4 and S-1)	72,270	66,349
Other	217,934	132,031
Total deferred credits and other	4,818,673	4,122,274
COMMITMENTS AND CONTINGENCIES (SEE NOTES)
TOTAL LIABILITIES AND EQUITY	13,111,018	12,392,998
ARIZONA PUBLIC SERVICE COMPANY
PROPERTY, PLANT AND EQUIPMENT (Notes 1, 6, 9 and 10)
Plant in service and held for future use	13,750,105	13,197,254
Accumulated depreciation and amortization	(4,706,462)	(4,510,591)
Net	9,043,643	8,686,663
Construction work in progress	496,745	459,316
Palo Verde sale leaseback, net of accumulated depreciation of $218,186 and $213,094 (Note 20)	132,864	137,956
Intangible assets, net of accumulated amortization of $372,573 and $329,444	170,416	184,768
Nuclear fuel, net of accumulated amortization of $113,375 and $85,270	118,098	108,794
Total property, plant and equipment	9,961,766	9,577,497
INVESTMENTS AND OTHER ASSETS
Nuclear decommissioning trust (Notes 14 and 23)	513,733	469,886
Assets from risk management activities (Note 18)	49,322	39,032
Other assets	30,551	71,428
Total investments and other assets	593,606	580,346
CURRENT ASSETS
Cash and cash equivalents	19,873	99,937
Customer and other receivables	280,100	288,323
Accrued unbilled revenues	125,239	103,292
Allowance for doubtful accounts	(3,748)	(7,646)
Materials and supplies (at average cost)	204,387	181,414
Fossil fuel (at average cost)	22,000	21,575
Assets from risk management activities (Note 18)	30,264	73,788
Deferred fuel and purchased power regulatory asset (Note 3)	27,549
Other regulatory assets (Note 3)	69,072	62,286
Deferred income taxes (Notes 4 and S-1)	111,503	105,042
Other current assets	29,355	25,135
Total current assets	915,594	953,146
DEFERRED DEBITS
Regulatory assets (Notes 1, 3, 4 and S-1)	1,352,079	986,370
Income tax receivable (Note 4 and S-1)	69,028	65,498	69,000
Unamortized debt issue costs	21,181	20,530
Other	118,983	88,490
Total deferred debits	1,561,271	1,160,888
TOTAL ASSETS	13,032,237	12,271,877
CAPITALIZATION
Common stock	178,162	178,162
Additional paid-in capital	2,379,696	2,379,696
Retained earnings	1,510,740	1,403,390
Accumulated other comprehensive (loss):
Pension and other postretirement benefits (Note 8)	(38,886)	(35,961)
Derivative instruments	(86,705)	(100,334)
Total shareholder equity	3,943,007	3,824,953
Noncontrolling interests (Note 20)	108,399	91,084
Total equity	4,051,406	3,916,037
Long-term debt less current maturities (Note 6)	2,828,507	2,948,991
Palo Verde sale leaseback lessor notes less current maturities (Notes 6 and 20)	65,547	96,803
Total capitalization	6,945,460	6,961,831
CURRENT LIABILITIES
Current maturities of long-term debt (Note 6)	477,435	456,879
Accounts payable	322,047	218,491
Accrued taxes	113,930	106,431
Accrued interest	54,611	54,638
Customer deposits	72,176	68,312
Liabilities from risk management activities (Note 18)	53,968	58,976
Deferred fuel and purchased power regulatory liability (Note 3)		58,442
Other regulatory liabilities (Note 3)	88,362	80,526
Other current liabilities	140,185	132,170
Total current liabilities	1,322,714	1,234,865
DEFERRED CREDITS AND OTHER
Deferred income taxes (Notes 4 and S-1)	1,952,608	1,895,654
Regulatory liabilities (Notes 1, 3, 4, and S-1)	737,332	614,063
Liability for asset retirements (Note 12)	279,643	328,571
Liabilities for pension and other postretirement benefits (Note 8)	1,222,542	770,611
Liabilities from risk management activities (Note 18)	82,495	65,390
Customer advances	116,805	121,645
Coal mine reclamation	117,896	117,243
Unrecognized tax benefits (Notes 4 and S-1)	72,073	65,363
Other	182,669	96,641
Total deferred credits and other	4,764,063	4,075,181
COMMITMENTS AND CONTINGENCIES (SEE NOTES)
TOTAL LIABILITIES AND EQUITY	$ 13,032,237	$ 12,271,877