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

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.

No definition available.

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

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

No definition available.

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

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

No definition available.

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

- References

No definition available.

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

Gain Contingency, New Claims Filed, Number

No definition available.

Name:	pnw_GainContingencyNewClaimsFiledNumber
Namespace Prefix:	pnw_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Gain Contingency, Number of Settlement Agreement Time Periods

No definition available.

Name:	pnw_GainContingencyNumberofSettlementAgreementTimePeriods
Namespace Prefix:	pnw_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Maximum Amount that Could be Incurred under Retrospective Assessment of NEIL Policies

No definition available.

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

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

No definition available.

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

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.

No definition available.

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

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

No definition available.

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

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

No definition available.

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

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.

No definition available.

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

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).

No definition available.

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

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

No definition available.

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

Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

No definition available.

Name:	us-gaap_LitigationSettlementAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Cash received for the settlement of litigation during the current period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

Name:	us-gaap_ProceedsFromLegalSettlements
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amount of change that payments under a contractual obligation might vary as facts and circumstances change.

No definition available.