SCHEDULE II RESERVE FOR UNCOLLECTIBLES (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Changes in reserve for uncollectibles
Additions, Charged to other accounts	$ 0
Reserve for uncollectibles. \| Pinnacle West
Changes in reserve for uncollectibles
Balance at beginning of period	4,709	4,573	3,383
Additions, Charged to cost and expenses	5,672	6,905	7,617
Deductions	6,633	6,769	6,427
Balance at end of period	$ 3,748	$ 4,709	$ 4,573

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Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e24092-122690

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- Definition

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- Definition

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- Definition

Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

+ References

+ Details

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