Cat Financial Financing Activities (Details 5) - Finance Receivables - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Customer
Impaired finance receivables
Recorded Investment With No Allowance Recorded	$ 530	$ 408
Unpaid Principal Balance With No Allowance Recorded	528	407
Related Allowance With No Allowance Recorded	0	0
Recorded Investment With An Allowance Recorded	256	193
Unpaid Principal Balance With An Allowance Recorded	265	191
Related Allowance With An Allowance Recorded	85	65
Recorded Investment, Total	786	601
Unpaid Principal Balance, Total	793	598
Related Allowance, Total	85	65
Average Recorded Investment With No Allowance Recorded	481	332	$ 333
Interest Income Recognized With No Allowance Recorded	18	10	11
Average Recorded Investment With An Allowance Recorded	211	268	274
Interest Income Recognized With An Allowance Recorded	7	10	12
Average Recorded Investment, Total	692	600	607
Interest Income Recognized, Total	25	20	23
Customer \| North America
Impaired finance receivables
Recorded Investment With No Allowance Recorded	10	12
Unpaid Principal Balance With No Allowance Recorded	10	12
Related Allowance With No Allowance Recorded	0	0
Recorded Investment With An Allowance Recorded	61	14
Unpaid Principal Balance With An Allowance Recorded	60	13
Related Allowance With An Allowance Recorded	22	4
Recorded Investment, Total	71	26
Unpaid Principal Balance, Total	70	25
Related Allowance, Total	22	4
Average Recorded Investment With No Allowance Recorded	18	12	20
Interest Income Recognized With No Allowance Recorded	1	1	1
Average Recorded Investment With An Allowance Recorded	34	9	9
Interest Income Recognized With An Allowance Recorded	0	0	0
Average Recorded Investment, Total	52	21	29
Interest Income Recognized, Total	1	1	1
Customer \| Europe
Impaired finance receivables
Recorded Investment With No Allowance Recorded	49	41
Unpaid Principal Balance With No Allowance Recorded	48	41
Related Allowance With No Allowance Recorded	0	0
Recorded Investment With An Allowance Recorded	7	11
Unpaid Principal Balance With An Allowance Recorded	7	10
Related Allowance With An Allowance Recorded	3	5
Recorded Investment, Total	56	52
Unpaid Principal Balance, Total	55	51
Related Allowance, Total	3	5
Average Recorded Investment With No Allowance Recorded	46	42	47
Interest Income Recognized With No Allowance Recorded	1	1	1
Average Recorded Investment With An Allowance Recorded	11	14	21
Interest Income Recognized With An Allowance Recorded	1	1	1
Average Recorded Investment, Total	57	56	68
Interest Income Recognized, Total	2	2	2
Customer \| Asia Pacific
Impaired finance receivables
Recorded Investment With No Allowance Recorded	3	1
Unpaid Principal Balance With No Allowance Recorded	2	1
Related Allowance With No Allowance Recorded	0	0
Recorded Investment With An Allowance Recorded	50	34
Unpaid Principal Balance With An Allowance Recorded	50	34
Related Allowance With An Allowance Recorded	8	4
Recorded Investment, Total	53	35
Unpaid Principal Balance, Total	52	35
Related Allowance, Total	8	4
Average Recorded Investment With No Allowance Recorded	2	2	3
Interest Income Recognized With No Allowance Recorded	0	0	0
Average Recorded Investment With An Allowance Recorded	37	35	22
Interest Income Recognized With An Allowance Recorded	3	2	1
Average Recorded Investment, Total	39	37	25
Interest Income Recognized, Total	3	2	1
Customer \| Mining
Impaired finance receivables
Recorded Investment With No Allowance Recorded	129	84
Unpaid Principal Balance With No Allowance Recorded	129	84
Related Allowance With No Allowance Recorded	0	0
Recorded Investment With An Allowance Recorded	0	11
Unpaid Principal Balance With An Allowance Recorded	0	11
Related Allowance With An Allowance Recorded	0	3
Recorded Investment, Total	129	95
Unpaid Principal Balance, Total	129	95
Related Allowance, Total	0	3
Average Recorded Investment With No Allowance Recorded	98	75	69
Interest Income Recognized With No Allowance Recorded	4	3	3
Average Recorded Investment With An Allowance Recorded	13	39	90
Interest Income Recognized With An Allowance Recorded	0	1	7
Average Recorded Investment, Total	111	114	159
Interest Income Recognized, Total	4	4	10
Customer \| Latin America
Impaired finance receivables
Recorded Investment With No Allowance Recorded	68	28
Unpaid Principal Balance With No Allowance Recorded	68	28
Related Allowance With No Allowance Recorded	0	0
Recorded Investment With An Allowance Recorded	93	53
Unpaid Principal Balance With An Allowance Recorded	104	53
Related Allowance With An Allowance Recorded	34	21
Recorded Investment, Total	161	81
Unpaid Principal Balance, Total	172	81
Related Allowance, Total	34	21
Average Recorded Investment With No Allowance Recorded	47	31	30
Interest Income Recognized With No Allowance Recorded	1	0	0
Average Recorded Investment With An Allowance Recorded	66	56	36
Interest Income Recognized With An Allowance Recorded	2	3	1
Average Recorded Investment, Total	113	87	66
Interest Income Recognized, Total	3	3	1
Customer \| Caterpillar Power Finance
Impaired finance receivables
Recorded Investment With No Allowance Recorded	271	242
Unpaid Principal Balance With No Allowance Recorded	271	241
Related Allowance With No Allowance Recorded	0	0
Recorded Investment With An Allowance Recorded	45	70
Unpaid Principal Balance With An Allowance Recorded	44	70
Related Allowance With An Allowance Recorded	18	28
Recorded Investment, Total	316	312
Unpaid Principal Balance, Total	315	311
Related Allowance, Total	18	28
Average Recorded Investment With No Allowance Recorded	270	170	164
Interest Income Recognized With No Allowance Recorded	11	5	6
Average Recorded Investment With An Allowance Recorded	50	115	96
Interest Income Recognized With An Allowance Recorded	1	3	2
Average Recorded Investment, Total	320	285	260
Interest Income Recognized, Total	12	8	8
Dealer
Impaired finance receivables
Recorded Investment, Total	$ 0	0
Average Recorded Investment, Total		$ 0	$ 0

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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=66008989&loc=d3e5212-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
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-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524

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Amount of allowance for credit losses related to recorded investment.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

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-Publisher FASB
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Amount of average investment of impaired financing receivables for which there is no 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 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

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