Cat Financial Financing Activities (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 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	$ 229		$ 229		$ 446
Unpaid Principal Balance With No Allowance Recorded	228		228		443
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	386		386		182
Unpaid Principal Balance With An Allowance Recorded	383		383		177
Related Allowance	87		87		70
Recorded Investment, Total	615		615		628
Unpaid Principal Balance, Total	611		611		620
Related Allowance, Total	87		87		70
Average Recorded Investment With No Allowance Recorded	275	468	358	414
Interest Income Recognized With No Allowance Recorded	2	3	9	7
Average Recorded Investment With An Allowance Recorded	314	262	232	247
Interest Income Recognized With An Allowance Recorded	5	2	9	5
Average Recorded Investment, Total	589	730	590	661
Interest Income Recognized, Total	7	5	18	12
Customer \| North America
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	15		15		23
Unpaid Principal Balance With No Allowance Recorded	15		15		22
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	7		7		13
Unpaid Principal Balance With An Allowance Recorded	7		7		13
Related Allowance	2		2		4
Recorded Investment, Total	22		22		36
Unpaid Principal Balance, Total	22		22		35
Related Allowance, Total	2		2		4
Average Recorded Investment With No Allowance Recorded	19	23	22	26
Interest Income Recognized With No Allowance Recorded	0	0	1	3
Average Recorded Investment With An Allowance Recorded	10	14	10	18
Interest Income Recognized With An Allowance Recorded	0	0	0	0
Average Recorded Investment, Total	29	37	32	44
Interest Income Recognized, Total	0	0	1	3
Customer \| Europe
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	46		46		48
Unpaid Principal Balance With No Allowance Recorded	46		46		47
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	33		33		20
Unpaid Principal Balance With An Allowance Recorded	32		32		19
Related Allowance	9		9		7
Recorded Investment, Total	79		79		68
Unpaid Principal Balance, Total	78		78		66
Related Allowance, Total	9		9		7
Average Recorded Investment With No Allowance Recorded	47	52	47	48
Interest Income Recognized With No Allowance Recorded	1	0	1	0
Average Recorded Investment With An Allowance Recorded	24	21	21	23
Interest Income Recognized With An Allowance Recorded	1	0	1	1
Average Recorded Investment, Total	71	73	68	71
Interest Income Recognized, Total	2	0	2	1
Customer \| Asia Pacific
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	0		0		7
Unpaid Principal Balance With No Allowance Recorded	0		0		7
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	22		22		16
Unpaid Principal Balance With An Allowance Recorded	22		22		16
Related Allowance	7		7		2
Recorded Investment, Total	22		22		23
Unpaid Principal Balance, Total	22		22		23
Related Allowance, Total	7		7		2
Average Recorded Investment With No Allowance Recorded	0	3	4	4
Interest Income Recognized With No Allowance Recorded	0	0	0	0
Average Recorded Investment With An Allowance Recorded	26	18	18	18
Interest Income Recognized With An Allowance Recorded	0	0	1	1
Average Recorded Investment, Total	26	21	22	22
Interest Income Recognized, Total	0	0	1	1
Customer \| Mining
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	10		10		134
Unpaid Principal Balance With No Allowance Recorded	10		10		134
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	144		144		0
Unpaid Principal Balance With An Allowance Recorded	142		142		0
Related Allowance	14		14		0
Recorded Investment, Total	154		154		134
Unpaid Principal Balance, Total	152		152		134
Related Allowance, Total	14		14		0
Average Recorded Investment With No Allowance Recorded	29	96	82	40
Interest Income Recognized With No Allowance Recorded	0	2	3	2
Average Recorded Investment With An Allowance Recorded	127	0	75	1
Interest Income Recognized With An Allowance Recorded	2	0	4	0
Average Recorded Investment, Total	156	96	157	41
Interest Income Recognized, Total	2	2	7	2
Customer \| Latin America
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	37		37		11
Unpaid Principal Balance With No Allowance Recorded	37		37		11
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	43		43		23
Unpaid Principal Balance With An Allowance Recorded	43		43		23
Related Allowance	14		14		6
Recorded Investment, Total	80		80		34
Unpaid Principal Balance, Total	80		80		34
Related Allowance, Total	14		14		6
Average Recorded Investment With No Allowance Recorded	37	14	29	11
Interest Income Recognized With No Allowance Recorded	0	0	0	0
Average Recorded Investment With An Allowance Recorded	27	53	24	44
Interest Income Recognized With An Allowance Recorded	1	1	1	2
Average Recorded Investment, Total	64	67	53	55
Interest Income Recognized, Total	1	1	1	2
Customer \| Caterpillar Power Finance
Impaired loans and finance leases
Recorded Investment With No Allowance Recorded	121		121		223
Unpaid Principal Balance With No Allowance Recorded	120		120		222
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	137		137		110
Unpaid Principal Balance With An Allowance Recorded	137		137		106
Related Allowance	41		41		51
Recorded Investment, Total	258		258		333
Unpaid Principal Balance, Total	257		257		328
Related Allowance, Total	41		41		51
Average Recorded Investment With No Allowance Recorded	143	280	174	285
Interest Income Recognized With No Allowance Recorded	1	1	4	2
Average Recorded Investment With An Allowance Recorded	100	156	84	143
Interest Income Recognized With An Allowance Recorded	1	1	2	1
Average Recorded Investment, Total	243	436	258	428
Interest Income Recognized, Total	2	2	6	3
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=35738203&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=35738203&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=35738203&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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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.

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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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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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