Cat Financial Financing Activities (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Receivables [Abstract]
Period after which collection of future income is considered as not probable (in days)	120 days
Customer
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	$ 402		$ 446
Unpaid Principal Balance With No Allowance Recorded	401		443
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	151		182
Unpaid Principal Balance With An Allowance Recorded	149		177
Related Allowance	50		70
Recorded Investment, Total	553		628
Unpaid Principal Balance, Total	550		620
Related Allowance, Total	50		70
Average Recorded Investment With No Allowance Recorded	435	371
Interest Income Recognized With No Allowance Recorded	5	1
Average Recorded Investment With An Allowance Recorded	173	283
Interest Income Recognized With An Allowance Recorded	1	2
Average Recorded Investment, Total	608	654
Interest Income Recognized, Total	6	3
Customer \| North America
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	24		23
Unpaid Principal Balance With No Allowance Recorded	23		22
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	8		13
Unpaid Principal Balance With An Allowance Recorded	8		13
Related Allowance	3		4
Recorded Investment, Total	32		36
Unpaid Principal Balance, Total	31		35
Related Allowance, Total	3		4
Average Recorded Investment With No Allowance Recorded	25	28
Interest Income Recognized With No Allowance Recorded	1	1
Average Recorded Investment With An Allowance Recorded	10	24
Interest Income Recognized With An Allowance Recorded	0	0
Average Recorded Investment, Total	35	52
Interest Income Recognized, Total	1	1
Customer \| Europe
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	47		48
Unpaid Principal Balance With No Allowance Recorded	47		47
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	17		20
Unpaid Principal Balance With An Allowance Recorded	16		19
Related Allowance	6		7
Recorded Investment, Total	64		68
Unpaid Principal Balance, Total	63		66
Related Allowance, Total	6		7
Average Recorded Investment With No Allowance Recorded	48	45
Interest Income Recognized With No Allowance Recorded	0	0
Average Recorded Investment With An Allowance Recorded	19	34
Interest Income Recognized With An Allowance Recorded	0	0
Average Recorded Investment, Total	67	79
Interest Income Recognized, Total	0	0
Customer \| Asia Pacific
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	5		7
Unpaid Principal Balance With No Allowance Recorded	5		7
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	11		16
Unpaid Principal Balance With An Allowance Recorded	11		16
Related Allowance	3		2
Recorded Investment, Total	16		23
Unpaid Principal Balance, Total	16		23
Related Allowance, Total	3		2
Average Recorded Investment With No Allowance Recorded	6	4
Interest Income Recognized With No Allowance Recorded	0	0
Average Recorded Investment With An Allowance Recorded	14	26
Interest Income Recognized With An Allowance Recorded	0	1
Average Recorded Investment, Total	20	30
Interest Income Recognized, Total	0	1
Customer \| Mining
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	133		134
Unpaid Principal Balance With No Allowance Recorded	133		134
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	32		0
Unpaid Principal Balance With An Allowance Recorded	32		0
Related Allowance	12		0
Recorded Investment, Total	165		134
Unpaid Principal Balance, Total	165		134
Related Allowance, Total	12		0
Average Recorded Investment With No Allowance Recorded	134	0
Interest Income Recognized With No Allowance Recorded	2	0
Average Recorded Investment With An Allowance Recorded	24	19
Interest Income Recognized With An Allowance Recorded	0	0
Average Recorded Investment, Total	158	19
Interest Income Recognized, Total	2	0
Customer \| Latin America
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	37		11
Unpaid Principal Balance With No Allowance Recorded	37		11
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	28		23
Unpaid Principal Balance With An Allowance Recorded	28		23
Related Allowance	8		6
Recorded Investment, Total	65		34
Unpaid Principal Balance, Total	65		34
Related Allowance, Total	8		6
Average Recorded Investment With No Allowance Recorded	17	9
Interest Income Recognized With No Allowance Recorded	0	0
Average Recorded Investment With An Allowance Recorded	24	52
Interest Income Recognized With An Allowance Recorded	0	1
Average Recorded Investment, Total	41	61
Interest Income Recognized, Total	0	1
Customer \| Caterpillar Power Finance
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	156		223
Unpaid Principal Balance With No Allowance Recorded	156		222
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	55		110
Unpaid Principal Balance With An Allowance Recorded	54		106
Related Allowance	18		51
Recorded Investment, Total	211		333
Unpaid Principal Balance, Total	210		328
Related Allowance, Total	18		51
Average Recorded Investment With No Allowance Recorded	205	285
Interest Income Recognized With No Allowance Recorded	2	0
Average Recorded Investment With An Allowance Recorded	82	128
Interest Income Recognized With An Allowance Recorded	1	0
Average Recorded Investment, Total	287	413
Interest Income Recognized, Total	3	0
Dealer
Impaired loans and finance leases
Recorded Investment, Total	0		0
Average Recorded Investment, Total	$ 0	$ 0

Amount of allowance for credit losses related to recorded investment

No definition available.

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

- Definition

This element represents the period after which collection of future income is considered as not probable.

+ References

No definition available.

+ Details

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- Details

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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5258-111524

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- Definition

Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

+ Details

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- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953550-111524

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

+ Details

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

- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

+ Details

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Period Type:	instant

- Definition

Amount of average investment of impaired financing receivables for which there is no related allowance for credit losses.

+ References

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of interest income, recognized on cash basis, on financing receivables, for which there is no related allowance for credit losses and are recognized as impaired.

+ References

+ Details

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- Definition

Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

+ References

+ Details

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- Definition

Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

+ References

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Period Type:	instant

- Definition

Amount of average investment of impaired financing receivables for which there is a related allowance for credit losses.

+ References

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- Definition

Amount of interest income on financing receivables, for which there is a related allowance for credit losses, recognized on a cash-basis method of accounting that the financing receivables were impaired.

+ References

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- Definition

Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

+ References

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- Definition

Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

+ References

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