SCHEDULE II - RESERVE FOR UNCOLLECTIBLES (Details) (Reserve for uncollectibles., USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
ARIZONA PUBLIC SERVICE COMPANY
Changes in reserve for uncollectibles
Balance at beginning of period	$ 3,203	$ 3,340	$ 3,748
Additions, Charged to cost and expenses	3,942	4,923	5,290
Additions, Charged to other accounts	0	0	0
Deductions	4,051	5,060	5,698
Balance at end of period	3,094	3,203	3,340
Pinnacle West
Changes in reserve for uncollectibles
Balance at beginning of period	3,203	3,340	3,748
Additions, Charged to cost and expenses	3,942	4,923	5,290
Additions, Charged to other accounts	0	0	0
Deductions	4,051	5,060	5,698
Balance at end of period	$ 3,094	$ 3,203	$ 3,340

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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 FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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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.

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