Name:	cbt_AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromNetInvestmentHedgesNetOfTax
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Derivative instruments frequency of cash settlements.

No definition available.

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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.

Name:	us-gaap_DerivativeLineItems
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Nominal or face amount used to calculate payment on derivative.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

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Fair value of all derivative assets designated as hedges of net investment in foreign operations.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624163-113959

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Fair value of all derivative liabilities designated as hedges of net investment in foreign operations.