Name:	us-gaap_CommitmentsAndContingenciesDisclosureAbstract
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The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82913245&loc=d3e12069-110248

Name:	us-gaap_GuaranteeObligationsCurrentCarryingValue
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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_GuaranteeObligationsLineItems
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Data Type:	xbrli:stringItemType
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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=82913245&loc=d3e12069-110248

Name:	us-gaap_GuaranteeObligationsMaximumExposure
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Unused amount of commitments to extend credit to customers.

No definition available.

Name:	us-gaap_UnusedCommitmentsToExtendCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=77990344&loc=d3e5710-111685

Name:	us-gaap_VariableInterestEntityConsolidatedCarryingAmountAssets
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

Name:	us-gaap_VariableInterestEntityConsolidatedCarryingAmountLiabilities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Name:	us-gaap_GuaranteeObligationsByNatureAxis=cat_GuaranteeWithDealerMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_GuaranteeObligationsByNatureAxis=cat_GuaranteeWithCustomersMember
Namespace Prefix:
Data Type:	na
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Period Type:

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cat_CustomerGuaranteesSupplierConsortiumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cat_ThirdPartyLogisticsBusinessMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: