Finance Receivables (Details 6) $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($) contracts	Mar. 31, 2017 USD ($) contracts	Dec. 31, 2017 USD ($)
Financing Receivable, Modifications
Remaining commitments	$ 0		$ 0
Finance receivables modified as TDRs
Number of Contracts \| contracts	18	30
Pre-TDR Recorded Investment	$ 41	$ 124
Post-TDR Recorded Investment	$ 41	$ 113
Customer \| North America
Finance receivables modified as TDRs
Number of Contracts \| contracts	13	9
Pre-TDR Recorded Investment	$ 6	$ 1
Post-TDR Recorded Investment	$ 6	$ 1
Customer \| Europe
Finance receivables modified as TDRs
Number of Contracts \| contracts	0	1
Pre-TDR Recorded Investment	$ 0	$ 0
Post-TDR Recorded Investment	$ 0	$ 0
Customer \| Asia/Pacific
Finance receivables modified as TDRs
Number of Contracts \| contracts	0	5
Pre-TDR Recorded Investment	$ 0	$ 39
Post-TDR Recorded Investment	$ 0	$ 30
Customer \| Mining
Finance receivables modified as TDRs
Number of Contracts \| contracts	1	2
Pre-TDR Recorded Investment	$ 29	$ 57
Post-TDR Recorded Investment	$ 29	$ 56
Customer \| Latin America
Finance receivables modified as TDRs
Number of Contracts \| contracts	1	7
Pre-TDR Recorded Investment	$ 3	$ 2
Post-TDR Recorded Investment	$ 3	$ 2
Customer \| Caterpillar Power Finance
Finance receivables modified as TDRs
Number of Contracts \| contracts	3	6
Pre-TDR Recorded Investment	$ 3	$ 25
Post-TDR Recorded Investment	$ 3	$ 24
Dealer
Finance receivables modified as TDRs
Number of Contracts \| contracts	0	0
Caterpillar Purchased Receivables
Finance receivables modified as TDRs
Number of Contracts \| contracts	0	0

Loan and finance lease receivables modified as TDRs

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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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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