Cat Financial Financing Activities (Details 3) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Dealer
Impaired finance receivables
Recorded Investment, Total	$ 0		$ 0
Finance Receivables \| Customer
Impaired finance receivables
Recorded Investment With No Allowance Recorded	341		424
Unpaid Principal Balance With No Allowance Recorded	353		435
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	630		518
Unpaid Principal Balance With An Allowance Recorded	630		530
Related Allowance With An Allowance Recorded	194		149
Recorded Investment, Total	971		942
Unpaid Principal Balance, Total	983		965
Related Allowance, Total	194		149
Average Recorded Investment With No Allowance Recorded	404	$ 535
Interest Income Recognized With No Allowance Recorded	5	5
Average Recorded Investment With An Allowance Recorded	540	271
Interest Income Recognized With An Allowance Recorded	3	3
Average Recorded Investment, Total	944	806
Interest Income Recognized, Total	8	8
Finance Receivables \| Customer \| North America
Impaired finance receivables
Recorded Investment With No Allowance Recorded	16		19
Unpaid Principal Balance With No Allowance Recorded	16		19
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	60		44
Unpaid Principal Balance With An Allowance Recorded	58		43
Related Allowance With An Allowance Recorded	21		17
Recorded Investment, Total	76		63
Unpaid Principal Balance, Total	74		62
Related Allowance, Total	21		17
Average Recorded Investment With No Allowance Recorded	17	10
Interest Income Recognized With No Allowance Recorded	0	0
Average Recorded Investment With An Allowance Recorded	51	61
Interest Income Recognized With An Allowance Recorded	1	0
Average Recorded Investment, Total	68	71
Interest Income Recognized, Total	1	0
Finance Receivables \| Customer \| Europe
Impaired finance receivables
Recorded Investment With No Allowance Recorded	7		45
Unpaid Principal Balance With No Allowance Recorded	7		45
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	49		9
Unpaid Principal Balance With An Allowance Recorded	49		8
Related Allowance With An Allowance Recorded	13		5
Recorded Investment, Total	56		54
Unpaid Principal Balance, Total	56		53
Related Allowance, Total	13		5
Average Recorded Investment With No Allowance Recorded	36	49
Interest Income Recognized With No Allowance Recorded	0	0
Average Recorded Investment With An Allowance Recorded	19	6
Interest Income Recognized With An Allowance Recorded	0	0
Average Recorded Investment, Total	55	55
Interest Income Recognized, Total	0	0
Finance Receivables \| Customer \| Asia Pacific
Impaired finance receivables
Recorded Investment With No Allowance Recorded	27		34
Unpaid Principal Balance With No Allowance Recorded	27		33
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	4		8
Unpaid Principal Balance With An Allowance Recorded	4		8
Related Allowance With An Allowance Recorded	1		2
Recorded Investment, Total	31		42
Unpaid Principal Balance, Total	31		41
Related Allowance, Total	1		2
Average Recorded Investment With No Allowance Recorded	31	9
Interest Income Recognized With No Allowance Recorded	1	0
Average Recorded Investment With An Allowance Recorded	6	45
Interest Income Recognized With An Allowance Recorded	0	1
Average Recorded Investment, Total	37	54
Interest Income Recognized, Total	1	1
Finance Receivables \| Customer \| Mining
Impaired finance receivables
Recorded Investment With No Allowance Recorded	50		121
Unpaid Principal Balance With No Allowance Recorded	50		121
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	67		0
Unpaid Principal Balance With An Allowance Recorded	67		0
Related Allowance With An Allowance Recorded	18		0
Recorded Investment, Total	117		121
Unpaid Principal Balance, Total	117		121
Related Allowance, Total	18		0
Average Recorded Investment With No Allowance Recorded	103	128
Interest Income Recognized With No Allowance Recorded	1	1
Average Recorded Investment With An Allowance Recorded	17	0
Interest Income Recognized With An Allowance Recorded	0	0
Average Recorded Investment, Total	120	128
Interest Income Recognized, Total	1	1
Finance Receivables \| Customer \| Latin America
Impaired finance receivables
Recorded Investment With No Allowance Recorded	46		45
Unpaid Principal Balance With No Allowance Recorded	46		45
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	71		95
Unpaid Principal Balance With An Allowance Recorded	71		106
Related Allowance With An Allowance Recorded	40		42
Recorded Investment, Total	117		140
Unpaid Principal Balance, Total	117		151
Related Allowance, Total	40		42
Average Recorded Investment With No Allowance Recorded	45	72
Interest Income Recognized With No Allowance Recorded	1	1
Average Recorded Investment With An Allowance Recorded	87	96
Interest Income Recognized With An Allowance Recorded	1	1
Average Recorded Investment, Total	132	168
Interest Income Recognized, Total	2	2
Finance Receivables \| Customer \| Caterpillar Power Finance
Impaired finance receivables
Recorded Investment With No Allowance Recorded	195		160
Unpaid Principal Balance With No Allowance Recorded	207		172
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	379		362
Unpaid Principal Balance With An Allowance Recorded	381		365
Related Allowance With An Allowance Recorded	101		83
Recorded Investment, Total	574		522
Unpaid Principal Balance, Total	588		537
Related Allowance, Total	101		$ 83
Average Recorded Investment With No Allowance Recorded	172	267
Interest Income Recognized With No Allowance Recorded	2	3
Average Recorded Investment With An Allowance Recorded	360	63
Interest Income Recognized With An Allowance Recorded	1	1
Average Recorded Investment, Total	532	330
Interest Income Recognized, Total	$ 3	$ 4

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+ 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)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
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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
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 310
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-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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