Income Taxes (Details) (USD $)	3 Months Ended	6 Months Ended
Mar. 31, 2011	Jun. 30, 2011	Dec. 31, 2010
Income Taxes
Income tax receivables		$ 67,970,000	$ 65,103,000
Phase-in period of corporate income tax rate reductions beginning in 2014 (in years)		4
Decrease in deferred income tax liabilities	53,000,000
Increase to regulatory liabilities	53,000,000
ARIZONA PUBLIC SERVICE COMPANY
Income Taxes
Income tax receivables		68,365,000	65,498,000
Period over which the cash refunds are not expected to be received (in months)		12
Increase to regulatory liabilities	$ 12,000,000

Period over which the income tax cash refunds are not expected to be received (in months).

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- Definition

Phase-in period of corporate income tax rate reductions beginning in 2014 by Arizona enacted legislation (H.B. 2001).

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ Details

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- Definition

Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 8
-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Section Appendix E
-Paragraph 289
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 7
-Section 03
-Paragraph 5
-Subparagraph c

+ Details

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Balance Type:	debit
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- Definition

The increase (decrease) during the reporting period in the account that represents the temporary difference that results from Income or Loss that is recognized for accounting purposes but not for tax purposes and vice versa.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

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- Definition

The increase (decrease) during the reporting period in regulated liabilities. Regulated liabilities are created when regulatory agency permits an entity to defer revenues to the balance sheet.

+ References

+ Details

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