Palo Verde Sale Leaseback Variable Interest Entities (Details) (USD $)	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Palo Verde Sale Leaseback Variable-Interest Entities
Increase in net income due to consolidation of Palo Verde Sale Leaseback Trusts	$ 7,426,000	$ 5,119,000	$ 20,041,000	$ 15,005,000
Amounts relating to the VIEs included in Condensed Consolidated Balance Sheets
Property plant and equipment, net of accumulated depreciation	133,832,000		133,832,000		137,956,000
Current maturities of long-term debt	876,363,000		876,363,000		631,879,000
Long-term debt less current maturities	83,130,000		83,130,000		96,803,000
Equity-Noncontrolling interests	108,910,000		108,910,000		91,899,000
Regulatory assets	977,975,000		977,975,000		986,370,000
ARIZONA PUBLIC SERVICE COMPANY
Palo Verde Sale Leaseback Variable-Interest Entities
Number of VIE lessor trusts	3		3
Lease payments per year			49,000,000
Increase in net income due to consolidation of Palo Verde Sale Leaseback Trusts	7,435,000	5,128,000	20,089,000	15,034,000
Amounts relating to the VIEs included in Condensed Consolidated Balance Sheets
Property plant and equipment, net of accumulated depreciation	133,832,000		133,832,000		137,956,000
Current maturities of long-term debt	876,363,000		876,363,000		456,879,000
Long-term debt less current maturities	83,130,000		83,130,000		96,803,000
Equity-Noncontrolling interests	108,564,000		108,564,000		91,084,000
Regulatory assets	977,975,000		977,975,000		986,370,000
ARIZONA PUBLIC SERVICE COMPANY \| Consolidation of VIEs
Palo Verde Sale Leaseback Variable-Interest Entities
Increase in net income due to consolidation of Palo Verde Sale Leaseback Trusts	7,000,000		20,000,000
Amounts relating to the VIEs included in Condensed Consolidated Balance Sheets
Property plant and equipment, net of accumulated depreciation	134,000,000		134,000,000		138,000,000
Current maturities of long-term debt	30,000,000		30,000,000		29,000,000
Long-term debt less current maturities	83,000,000		83,000,000		97,000,000
Equity-Noncontrolling interests	109,000,000		109,000,000		91,000,000
Regulatory assets	34,000,000		34,000,000		33,000,000
Maximum payment to the VIEs' noncontrolling equity participants upon the occurrence of certain unlikely events			145,000,000
VIE debt to be assumed upon the occurrence of certain unlikely events			$ 113,000,000

Number of VIE lessor trusts with whom agreements have been made to sell and lease back interests in certain nuclear generating assets and related common facilities.

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Variable Interest entity long term debt less current maturities.

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The amount of exposure to loss, upon the occurrence of certain events, in the form of assumed debt that is already reflected in the Consolidated Balance Sheets, as a result of involvement with the Variable Interest Entity (VIE).

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest).

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The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

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