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

No definition available.

Name:	pnw_AnnualPaymentLimitationWithRespectToMaximumPotentialRetrospectiveAssessment
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Data Type:	xbrli:monetaryItemType
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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.

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Balance Type:	credit
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Fuel and Purchased Power Commitments and Purchase Obligations [Abstract]

No definition available.

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Gain Contingency, New Claims Filed, Number

No definition available.

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Data Type:	xbrli:integerItemType
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Gain Contingency, Number of Settlement Agreement Time Periods

No definition available.

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Data Type:	xbrli:integerItemType
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Maximum Amount that Could be Incurred under Retrospective Assessment of NEIL Policies

No definition available.

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Data Type:	xbrli:monetaryItemType
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Represents the maximum assessment per reactor under the program for each nuclear incident.

No definition available.

Name:	pnw_MaximumAssessmentPerReactorForEachNuclearIncident
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Data Type:	xbrli:monetaryItemType
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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.

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

No definition available.

Name:	pnw_MaximumInsuranceCoveragePerIncident
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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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
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Data Type:	xbrli:monetaryItemType
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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.

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Palo Verde Nuclear Generating Station [Abstract]

No definition available.

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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
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Data Type:	xbrli:durationItemType
Balance Type:	na
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Represents the remaining nuclear liability insurance that is provided through mandatory industry wide retrospective assessment program.

No definition available.

Name:	pnw_RemainingNuclearLiabilityInsuranceThroughMandatoryIndustryWideRetrospectiveAssessmentProgram
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Data Type:	xbrli:monetaryItemType
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The net present value of an unrecorded unconditional purchase obligation as of the balance sheet date.

No definition available.

Name:	pnw_UnrecordedUnconditionalPurchaseObligationPresentValue
Namespace Prefix:	pnw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

No definition available.

Name:	us-gaap_LitigationSettlementAmount
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=73718637&loc=d3e25336-109308

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Data Type:	xbrli:monetaryItemType
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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

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Data Type:	xbrli:monetaryItemType
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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Data Type:	xbrli:monetaryItemType
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The amount purchased during the period under an unrecorded unconditional purchase obligation (for example, under the take-or-pay or throughput contract).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=73718637&loc=d3e25336-109308

Name:	us-gaap_UnrecordedUnconditionalPurchaseObligationPurchases
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Data Type:	xbrli:monetaryItemType
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Name:	dei_LegalEntityAxis=pnw_ArizonaPublicServiceCompanyMember
Namespace Prefix:
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Name:	us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis=us-gaap_PublicUtilitiesInventoryFuelMember
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Name:	us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis=pnw_RenewableEnergyCreditsMember
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Data Type:	na
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Name:	us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis=pnw_CoalMineReclamationObligationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis=pnw_CoalMineReclamationBalanceSheetObligationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	dei_LegalEntityAxis=pnw_A4CAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_LitigationCaseAxis=pnw_BreachofContractforDisposalofSpentNuclearFuelandorHighLevelRadioactiveWasteMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_LitigationCaseAxis=pnw_ArizonaPublicServiceCompanyandPaloVerdeOwnersvs.UnitedStatesDepartmentofEnergySpentNuclearFuelandWasteDisposalMember
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Data Type:	na
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