Cat Financial Financing Activities (Details 5) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015 Contracts	Mar. 31, 2014 Contracts	Dec. 31, 2014
Customer
Finance receivables modified as TDRs
Number of Contracts (in contracts)	5	9
Pre-TDR Outstanding Recorded Investment	$ 84	$ 48
Post-TDR Outstanding Recorded Investment	81	46
TDRs with a payment default which had been modified within twelve months prior to the default date
Number of Contracts (in contracts)	5	14
Post-TDR Recorded Investment	1	2
Customer \| North America
Finance receivables modified as TDRs
Number of Contracts (in contracts)	3	3
Pre-TDR Outstanding Recorded Investment	1	2
Post-TDR Outstanding Recorded Investment	1	2
TDRs with a payment default which had been modified within twelve months prior to the default date
Number of Contracts (in contracts)	4	7
Post-TDR Recorded Investment	1	1
Customer \| Europe
Finance receivables modified as TDRs
Number of Contracts (in contracts)	0	3
Pre-TDR Outstanding Recorded Investment	0	5
Post-TDR Outstanding Recorded Investment	0	5
TDRs with a payment default which had been modified within twelve months prior to the default date
Number of Contracts (in contracts)	0	7
Post-TDR Recorded Investment	0	1
Customer \| Mining
Finance receivables modified as TDRs
Number of Contracts (in contracts)	0	1
Pre-TDR Outstanding Recorded Investment	0	11
Post-TDR Outstanding Recorded Investment	0	10
Customer \| Latin America
Finance receivables modified as TDRs
Number of Contracts (in contracts)	0	1
Pre-TDR Outstanding Recorded Investment	0	29
Post-TDR Outstanding Recorded Investment	0	28
TDRs with a payment default which had been modified within twelve months prior to the default date
Number of Contracts (in contracts)	1	0
Post-TDR Recorded Investment	0	0
Customer \| Caterpillar Power Finance
Finance receivables modified as TDRs
Number of Contracts (in contracts)	2	1
Pre-TDR Outstanding Recorded Investment	83	1
Post-TDR Outstanding Recorded Investment	80	1
Dealer
Finance receivables modified as TDRs
Number of Contracts (in contracts)	0
Finance Receivable [Member] \| Customer
Finance receivables modified as TDRs
Remaining Commitments	$ 0		$ 0

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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=35738203&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

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953682-111524

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

+ Details

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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=25495931&loc=d3e18794-111554

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