Cat Financial Financing Activities (Details 5) $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($) Contracts	Mar. 31, 2017 USD ($) Contracts	Dec. 31, 2017 USD ($)
Customer
Finance receivables modified as TDRs
Number of Contracts (in contracts) \| Contracts	18	30
Pre-TDR Outstanding Recorded Investment	$ 41	$ 124
Post-TDR Outstanding Recorded Investment	$ 41	$ 113
Customer \| North America
Finance receivables modified as TDRs
Number of Contracts (in contracts) \| Contracts	13	9
Pre-TDR Outstanding Recorded Investment	$ 6	$ 1
Post-TDR Outstanding Recorded Investment	$ 6	$ 1
Customer \| Europe
Finance receivables modified as TDRs
Number of Contracts (in contracts) \| Contracts	0	1
Pre-TDR Outstanding Recorded Investment	$ 0	$ 0
Post-TDR Outstanding Recorded Investment	$ 0	$ 0
Customer \| Asia Pacific
Finance receivables modified as TDRs
Number of Contracts (in contracts) \| Contracts	0	5
Pre-TDR Outstanding Recorded Investment	$ 0	$ 39
Post-TDR Outstanding Recorded Investment	$ 0	$ 30
Customer \| Mining
Finance receivables modified as TDRs
Number of Contracts (in contracts) \| Contracts	1	2
Pre-TDR Outstanding Recorded Investment	$ 29	$ 57
Post-TDR Outstanding Recorded Investment	$ 29	$ 56
Customer \| Latin America
Finance receivables modified as TDRs
Number of Contracts (in contracts) \| Contracts	1	7
Pre-TDR Outstanding Recorded Investment	$ 3	$ 2
Post-TDR Outstanding Recorded Investment	$ 3	$ 2
Customer \| Caterpillar Power Finance
Finance receivables modified as TDRs
Number of Contracts (in contracts) \| Contracts	3	6
Pre-TDR Outstanding Recorded Investment	$ 3	$ 25
Post-TDR Outstanding Recorded Investment	3	$ 24
Dealer
Loan receivables
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest	$ 73		$ 0
Finance receivables modified as TDRs
Number of Contracts (in contracts) \| Contracts	0	0
Finance Receivables \| Customer
Loan receivables
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest	$ 635		683
Finance receivables modified as TDRs
Remaining Commitments	0		0
Finance Receivables \| Customer \| North America
Loan receivables
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest	50		38
Finance Receivables \| Customer \| Europe
Loan receivables
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest	50		37
Finance Receivables \| Customer \| Asia Pacific
Loan receivables
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest	8		10
Finance Receivables \| Customer \| Mining
Loan receivables
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest	14		63
Finance Receivables \| Customer \| Latin America
Loan receivables
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest	174		192
Finance Receivables \| Customer \| Caterpillar Power Finance
Loan receivables
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest	$ 339		$ 343

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+ References

No definition available.

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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- Definition

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- Definition

Reflects the unfunded portion of contractual agreements to lend funds to borrowers for loans whose terms have been modified by troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18794-111554

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- Definition

Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

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