v2.4.0.6

Commitments and Contingencies (Details) (ARIZONA PUBLIC SERVICE COMPANY, USD $)	0 Months Ended	3 Months Ended
	Apr. 02, 2013	Mar. 31, 2013 item
ARIZONA PUBLIC SERVICE COMPANY
Palo Verde Nuclear Generating Station
Estimated share of the costs related to on-site interim storage of spent nuclear fuel		$ 122,000,000
Regulatory liability of amounts recovered in retail rates in excess of amounts spent for on-site interim spent fuel storage		43,000,000
Maximum insurance against public liability per occurrence for a nuclear incident		12,600,000,000
Maximum available nuclear liability insurance		375,000,000
Remaining nuclear liability insurance through mandatory industry wide retrospective assessment program		12,200,000,000
Maximum assessment per reactor for each nuclear incident		118,000,000
Annual limit per incident with respect to maximum assessment		18,000,000
Number of VIE lessor trusts		3
Maximum potential assessment per incident of APS		103,000,000
Annual payment limitation with respect to maximum potential assessment		15,000,000
Amount of "all risk" (including nuclear hazards) insurance for property damage to, and decontamination of, property at Palo Verde		2,750,000,000
Sublimit for non-nuclear property damage losses which has been imposed to the primary policy offered	1,500,000,000
Sublimit for non-nuclear losses which has been imposed to the accidental outage policy	327,600,000
Maximum amount that APS could incur under the current NEIL policies for each retrospective assessment		18,000,000
Collateral assurance provided based on rating triggers		$ 48,000,000
Period to provide collateral assurance based on rating triggers		20 days

Represents the amount of sublimit for non-nuclear losses which has been imposed to the accidental outage policy during the reporting period.

+ References

No definition available.

+ Details

Name:	pnw_AcccidentalOutagePolicySublimitForNonNuclearLosses
Namespace Prefix:	pnw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the "all risk" (including nuclear hazards) insurance for property damage to, and decontamination of, property at Palo Verde of which a substantial portion must first be applied to stabilization and decontamination.

+ References

No definition available.

+ Details

Name:	pnw_AllRiskInsuranceForPropertyDamageAndDecontaminationAtPaloVerde
Namespace Prefix:	pnw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the annual limit per incident with respect to the maximum assessment per reactor under the program for each nuclear incident, to be periodically adjusted for inflation.

+ References

No definition available.

+ Details

Name:	pnw_AnnualLimitPerIncidentWithRespectToMaximumAssessment
Namespace Prefix:	pnw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the annual payment limitation with respect to maximum potential assessment.

+ References

No definition available.

+ Details

Name:	pnw_AnnualPaymentLimitationWithRespectToMaximumPotentialAssessment
Namespace Prefix:	pnw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the collateral assurance provided that depends upon rating triggers such as a rating downgrade to non-investment grade under NEIL policies.

+ References

No definition available.

+ Details

Name:	pnw_CollateralAssuranceBasedOnRatingTriggers
Namespace Prefix:	pnw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	pnw_CommitmentsAndContingenciesLineItems
Namespace Prefix:	pnw_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the estimated share of costs related to the on-site interim storage of spent nuclear fuel, which is to be incurred over the current life of Palo Verde with respect to the Palo Verde Nuclear Generating Station.

+ References

No definition available.

+ Details

Name:	pnw_EstimatedShareOfCostsRelatedToOnSiteInterimStorageOfSpentNuclearFuel
Namespace Prefix:	pnw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the maximum amount APS could incur under the current NEIL (Nuclear Electric Insurance Limited) policies for each retrospective assessment declared by NEIL's Board of Directors due to losses.

+ References

No definition available.

+ Details

Name:	pnw_MaximumAmountThatCouldBeIncurredUnderRetrospectiveAssessmentOfNEILPolicies
Namespace Prefix:	pnw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the maximum assessment per reactor under the program for each nuclear incident.

+ References

No definition available.

+ Details

Name:	pnw_MaximumAssessmentPerReactorForEachNuclearIncident
Namespace Prefix:	pnw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the maximum available nuclear liability insurance which is provided by commercial insurance carriers, maintained by Palo Verde as required by the Price Anderson Nuclear Industries Indemnity Act.

+ References

No definition available.

+ Details

Name:	pnw_MaximumAvailableNuclearLiabilityInsurance
Namespace Prefix:	pnw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the maximum insurance amount against public liability per occurrence for a nuclear incident.

+ References

No definition available.

+ Details

Name:	pnw_MaximumInsuranceCoveragePerIncident
Namespace Prefix:	pnw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the maximum potential assessment per incident based on the interest of APS in the three Palo Verde units.

+ References

No definition available.

+ Details

Name:	pnw_MaximumPotentialAssessmentPerIncident
Namespace Prefix:	pnw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

Name:	pnw_NumberOfVIELessorTrusts
Namespace Prefix:	pnw_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the period to provide collateral assurance based on rating triggers such as a rating downgrade to non-investment grade under NEIL policies (in days).

+ References

No definition available.

+ Details

Name:	pnw_PeriodToProvideCollateralAssuranceBasedOnRatingTriggers
Namespace Prefix:	pnw_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the amount of sublimit for non-nuclear property damage losses which has been imposed to the primary policy offered during the reporting period.

+ References

No definition available.

+ Details

Name:	pnw_PrimaryPolicyOfferedSublimitForNonNuclearPropertyDamageLosses
Namespace Prefix:	pnw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the remaining nuclear liability insurance that is provided through mandatory industry wide retrospective assessment program.

+ References

No definition available.

+ Details

Name:	pnw_RemainingNuclearLiabilityInsuranceThroughMandatoryIndustryWideRetrospectiveAssessmentProgram
Namespace Prefix:	pnw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 71

-Paragraph 11

-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.

+ Details

Name:	us-gaap_RegulatoryLiabilities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

ARIZONA PUBLIC SERVICE CO 10-Q