Cat Financial Financing Activities (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
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	$ 523		$ 523		$ 378
Unpaid Principal Balance With No Allowance Recorded	520		520		377
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	213		213		215
Unpaid Principal Balance With An Allowance Recorded	202		202		207
Related Allowance	60		60		54
Recorded Investment, Total	736		736		593
Unpaid Principal Balance, Total	722		722		584
Related Allowance, Total	60		60		54
Average Recorded Investment With No Allowance Recorded	468	323	414	323
Interest Income Recognized With No Allowance Recorded	3	2	7	5
Average Recorded Investment With An Allowance Recorded	262	210	247	177
Interest Income Recognized With An Allowance Recorded	2	2	5	3
Average Recorded Investment, Total	730	533	661	500
Interest Income Recognized, Total	5	4	12	8
Customer \| North America
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	20		20		28
Unpaid Principal Balance With No Allowance Recorded	19		19		27
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	16		16		25
Unpaid Principal Balance With An Allowance Recorded	14		14		23
Related Allowance	4		4		7
Recorded Investment, Total	36		36		53
Unpaid Principal Balance, Total	33		33		50
Related Allowance, Total	4		4		7
Average Recorded Investment With No Allowance Recorded	23	41	26	56
Interest Income Recognized With No Allowance Recorded	0	1	3	2
Average Recorded Investment With An Allowance Recorded	14	25	18	25
Interest Income Recognized With An Allowance Recorded	0	0	0	0
Average Recorded Investment, Total	37	66	44	81
Interest Income Recognized, Total	0	1	3	2
Customer \| Europe
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	53		53		45
Unpaid Principal Balance With No Allowance Recorded	52		52		45
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	19		19		28
Unpaid Principal Balance With An Allowance Recorded	15		15		26
Related Allowance	7		7		11
Recorded Investment, Total	72		72		73
Unpaid Principal Balance, Total	67		67		71
Related Allowance, Total	7		7		11
Average Recorded Investment With No Allowance Recorded	52	45	48	45
Interest Income Recognized With No Allowance Recorded	0	0	0	0
Average Recorded Investment With An Allowance Recorded	21	27	23	26
Interest Income Recognized With An Allowance Recorded	0	1	1	1
Average Recorded Investment, Total	73	72	71	71
Interest Income Recognized, Total	0	1	1	1
Customer \| Asia Pacific
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	2		2		2
Unpaid Principal Balance With No Allowance Recorded	2		2		2
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	22		22		19
Unpaid Principal Balance With An Allowance Recorded	22		22		19
Related Allowance	6		6		4
Recorded Investment, Total	24		24		21
Unpaid Principal Balance, Total	24		24		21
Related Allowance, Total	6		6		4
Average Recorded Investment With No Allowance Recorded	3	3	4	4
Interest Income Recognized With No Allowance Recorded	0	0	0	0
Average Recorded Investment With An Allowance Recorded	18	15	18	13
Interest Income Recognized With An Allowance Recorded	0	0	1	1
Average Recorded Investment, Total	21	18	22	17
Interest Income Recognized, Total	0	0	1	1
Customer \| Mining
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	127		127		1
Unpaid Principal Balance With No Allowance Recorded	127		127		1
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	0		0		0
Unpaid Principal Balance With An Allowance Recorded	0		0		0
Related Allowance	0		0		0
Recorded Investment, Total	127		127		1
Unpaid Principal Balance, Total	127		127		1
Related Allowance, Total	0		0		0
Average Recorded Investment With No Allowance Recorded	96	9	40	8
Interest Income Recognized With No Allowance Recorded	2	1	2	1
Average Recorded Investment With An Allowance Recorded	0	0	1	0
Interest Income Recognized With An Allowance Recorded	0	0	0	0
Average Recorded Investment, Total	96	9	41	8
Interest Income Recognized, Total	2	1	2	1
Customer \| Latin America
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	16		16		7
Unpaid Principal Balance With No Allowance Recorded	16		16		7
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	62		62		30
Unpaid Principal Balance With An Allowance Recorded	62		62		30
Related Allowance	18		18		8
Recorded Investment, Total	78		78		37
Unpaid Principal Balance, Total	78		78		37
Related Allowance, Total	18		18		8
Average Recorded Investment With No Allowance Recorded	14	6	11	6
Interest Income Recognized With No Allowance Recorded	0	0	0	0
Average Recorded Investment With An Allowance Recorded	53	37	44	26
Interest Income Recognized With An Allowance Recorded	1	1	2	1
Average Recorded Investment, Total	67	43	55	32
Interest Income Recognized, Total	1	1	2	1
Customer \| Caterpillar Power Finance
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	305		305		295
Unpaid Principal Balance With No Allowance Recorded	304		304		295
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	94		94		113
Unpaid Principal Balance With An Allowance Recorded	89		89		109
Related Allowance	25		25		24
Recorded Investment, Total	399		399		408
Unpaid Principal Balance, Total	393		393		404
Related Allowance, Total	25		25		24
Average Recorded Investment With No Allowance Recorded	280	219	285	204
Interest Income Recognized With No Allowance Recorded	1	0	2	2
Average Recorded Investment With An Allowance Recorded	156	106	143	87
Interest Income Recognized With An Allowance Recorded	1	0	1	0
Average Recorded Investment, Total	436	325	428	291
Interest Income Recognized, Total	2	0	3	2
Dealer
Impaired loans and finance leases
Recorded Investment, Total	0		0		0
Average Recorded Investment, Total	$ 0	$ 0	$ 0	$ 0

Amount of allowance for credit losses related to recorded investment

No definition available.

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- Definition

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

+ References

No definition available.

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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

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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

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- Definition

Amount of allowance for credit losses related to recorded investment.

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- Definition

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

+ References

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- Definition

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

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- 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

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

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

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

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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.

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

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

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