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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.

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

No definition available.

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Asset Purchase Agreement, Option To Purchase, Ownership Interest, Percentage

No definition available.

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Asset Purchase Agreement, Option to Purchase, Ownership Interest, Percentage

No definition available.

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Asset Purchase Agreement, Proceeds From Operating An Maintenance Cost Reimbursement

No definition available.

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Asset Purchase Agreement, Site Contingency, Increase In Loss Exposure Not Accrued, Best Estimate

No definition available.

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Asset Purchase Power Agreement

No definition available.

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Balance Type:	na
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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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- References

No definition available.

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Costs related to site-wide groundwater remedial investigation and feasibility study work plan because subsidiary has been found to be potentially responsible parties ("PRPs") with liability for cleanup of hazardous substances that contaminates the soil, water or air, under the Comprehensive Environmental Response, Compensation and Liability Act ("Superfund").

No definition available.

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Costs Related to Oversight and Remedial Investigation Of Superfund Site

No definition available.

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Financing Agreement of Sponsor Equity

No definition available.

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Gain Contingency, New Claims Filed, Number

No definition available.

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

No definition available.

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

No definition available.

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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.

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Data Type:	xbrli:monetaryItemType
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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.

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Non Recourse Construction Financing Agreement

No definition available.

Name:	pnw_NonRecourseConstructionFinancingAgreement
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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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Represents the percentage of share of the cost of control acquired by the entity.

No definition available.

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Data Type:	dtr-types1:percentItemType
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Production Tax Credit Guarantees

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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Public Utility, Project, Plant Capacity

No definition available.

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Data Type:	dtr-types1:powerItemType
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Recommended rate adjustment, annualized customer impact, cost deferrals

No definition available.

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Recommended Rate Adjustment, Annualized Customer Impact, Disallowance Of Investments

No definition available.

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

No definition available.

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Surety Bonds Expiring, Amount

No definition available.

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Unrecorded Unconditional Purchase Obligation, Reduction Due To Termination

No definition available.

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481664/323-10-45-1

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481664/323-10-45-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481687/323-10-50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 1
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-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 25
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-25

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

No definition available.

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Amount awarded from other party in judgment or settlement of litigation.

No definition available.

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Amount awarded to other party in judgment or settlement of litigation.

No definition available.

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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/disclosureRef
-Topic 440
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482648/440-10-50-4

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