Name:	pnw_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnOtherPostretirementBenefitsExpense
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The effect of a one-percentage-point increase in the assumed health care cost trend rates on the other postretirement benefits expense, after consideration of amount capitalized or billed to electric plant participants.

No definition available.

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Defined Benefit Plan, Post-65 Health Care Cost Trend Rate Assumed for Next Fiscal Year, Used in Calculating Benefit Costs

No definition available.

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Defined Benefit Plan, Post-65 Health Care Cost Trend Rate Assumed for Next Fiscal Year, Used in Calculating Benefit Obligation

No definition available.

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Defined Benefit Plan, Pre-65 Health Care Cost Trend Rate Assumed for Next Fiscal Year

No definition available.

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Defined Benefit Plan, Pre-65 Health Care Cost Trend Rate Assumed for Next Fiscal Year, Used in Calculating Benefit Obligation

No definition available.

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Defined Benefit Plan, Pre-65 Participant, Period after which Rate Reaches Ultimate Trend Rate, used in Calculating Benefit Costs

No definition available.

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Defined Benefit Plan, Pre-65 Participant, Period after which Rate Reaches Ultimate Trend Rate, used in Calculating Benefit Obligation

No definition available.

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Defined Benefit Plan, Ultimate Health Care Cost Trend Rate used in Calculating Benefit Obligations

No definition available.

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Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(2)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

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Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(2)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- References

No definition available.

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- References

No definition available.

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Amount of decrease in accumulated postretirement benefit obligation from one-percentage-point decrease in assumed health care cost trend rate.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (m)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Amount of decrease in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point decrease in assumed health care cost trend rate.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Amount of increase in accumulated postretirement benefit obligation from one-percentage-point increase in assumed health care cost trend rate.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of increase in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point increase in assumed health care cost trend rate.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (m)
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Ultimate trend rate for health care cost for defined benefit postretirement plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (l)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- References

No definition available.