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Represents the percentage change in assets allocation from return seeking to liability hedging due to change in funding level under the defined benefit plan.

No definition available.

Name:	crs_DefinedBenefitPlanPercentageChangeInTargetAssetAllocationsDueToChangeInFundingLevel
Namespace Prefix:	crs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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-Publisher FASB
-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

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

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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.

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

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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.

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

Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Amount of cost for defined contribution plan.

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Namespace Prefix:
Data Type:	na
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Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_RetirementPlanTaxStatusAxis=us-gaap_QualifiedPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_RetirementPlanTaxStatusAxis=us-gaap_NonqualifiedPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_RetirementPlanTypeAxis=us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Data Type:	na
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