Cat Financial Financing Activities (Details 3) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Dealer
Impaired finance receivables
Recorded Investment, Total	$ 0		$ 0		$ 0
Finance Receivables \| Customer
Impaired finance receivables
Recorded Investment With No Allowance Recorded	469		469		530
Unpaid Principal Balance With No Allowance Recorded	484		484		528
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	400		400		256
Unpaid Principal Balance With An Allowance Recorded	413		413		265
Related Allowance With An Allowance Recorded	100		100		85
Recorded Investment, Total	869		869		786
Unpaid Principal Balance, Total	897		897		793
Related Allowance, Total	100		100		85
Average Recorded Investment With No Allowance Recorded	458	$ 504	512	$ 458
Interest Income Recognized With No Allowance Recorded	5	6	18	13
Average Recorded Investment With An Allowance Recorded	431	216	335	197
Interest Income Recognized With An Allowance Recorded	5	1	10	5
Average Recorded Investment, Total	889	720	847	655
Interest Income Recognized, Total	10	7	28	18
Finance Receivables \| Customer \| North America
Impaired finance receivables
Recorded Investment With No Allowance Recorded	16		16		10
Unpaid Principal Balance With No Allowance Recorded	21		21		10
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	36		36		61
Unpaid Principal Balance With An Allowance Recorded	35		35		60
Related Allowance With An Allowance Recorded	13		13		22
Recorded Investment, Total	52		52		71
Unpaid Principal Balance, Total	56		56		70
Related Allowance, Total	13		13		22
Average Recorded Investment With No Allowance Recorded	14	24	12	19
Interest Income Recognized With No Allowance Recorded	1	0	1	1
Average Recorded Investment With An Allowance Recorded	44	42	52	28
Interest Income Recognized With An Allowance Recorded	0	0	1	0
Average Recorded Investment, Total	58	66	64	47
Interest Income Recognized, Total	1	0	2	1
Finance Receivables \| Customer \| Europe
Impaired finance receivables
Recorded Investment With No Allowance Recorded	47		47		49
Unpaid Principal Balance With No Allowance Recorded	47		47		48
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	8		8		7
Unpaid Principal Balance With An Allowance Recorded	8		8		7
Related Allowance With An Allowance Recorded	5		5		3
Recorded Investment, Total	55		55		56
Unpaid Principal Balance, Total	55		55		55
Related Allowance, Total	5		5		3
Average Recorded Investment With No Allowance Recorded	47	49	48	45
Interest Income Recognized With No Allowance Recorded	0	1	1	1
Average Recorded Investment With An Allowance Recorded	6	10	6	11
Interest Income Recognized With An Allowance Recorded	0	0	0	0
Average Recorded Investment, Total	53	59	54	56
Interest Income Recognized, Total	0	1	1	1
Finance Receivables \| Customer \| Asia Pacific
Impaired finance receivables
Recorded Investment With No Allowance Recorded	32		32		3
Unpaid Principal Balance With No Allowance Recorded	31		31		2
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	25		25		50
Unpaid Principal Balance With An Allowance Recorded	25		25		50
Related Allowance With An Allowance Recorded	3		3		8
Recorded Investment, Total	57		57		53
Unpaid Principal Balance, Total	56		56		52
Related Allowance, Total	3		3		8
Average Recorded Investment With No Allowance Recorded	30	1	22	2
Interest Income Recognized With No Allowance Recorded	1	0	2	0
Average Recorded Investment With An Allowance Recorded	28	35	35	34
Interest Income Recognized With An Allowance Recorded	1	0	2	2
Average Recorded Investment, Total	58	36	57	36
Interest Income Recognized, Total	2	0	4	2
Finance Receivables \| Customer \| Mining
Impaired finance receivables
Recorded Investment With No Allowance Recorded	127		127		129
Unpaid Principal Balance With No Allowance Recorded	125		125		129
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 With An Allowance Recorded	0		0		0
Recorded Investment, Total	127		127		129
Unpaid Principal Balance, Total	125		125		129
Related Allowance, Total	0		0		0
Average Recorded Investment With No Allowance Recorded	128	90	128	84
Interest Income Recognized With No Allowance Recorded	1	2	5	3
Average Recorded Investment With An Allowance Recorded	0	19	0	15
Interest Income Recognized With An Allowance Recorded	0	0	0	0
Average Recorded Investment, Total	128	109	128	99
Interest Income Recognized, Total	1	2	5	3
Finance Receivables \| Customer \| Latin America
Impaired finance receivables
Recorded Investment With No Allowance Recorded	60		60		68
Unpaid Principal Balance With No Allowance Recorded	60		60		68
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	92		92		93
Unpaid Principal Balance With An Allowance Recorded	104		104		104
Related Allowance With An Allowance Recorded	35		35		34
Recorded Investment, Total	152		152		161
Unpaid Principal Balance, Total	164		164		172
Related Allowance, Total	35		35		34
Average Recorded Investment With No Allowance Recorded	68	58	69	39
Interest Income Recognized With No Allowance Recorded	1	0	2	0
Average Recorded Investment With An Allowance Recorded	102	67	101	59
Interest Income Recognized With An Allowance Recorded	1	1	3	2
Average Recorded Investment, Total	170	125	170	98
Interest Income Recognized, Total	2	1	5	2
Finance Receivables \| Customer \| Caterpillar Power Finance
Impaired finance receivables
Recorded Investment With No Allowance Recorded	187		187		271
Unpaid Principal Balance With No Allowance Recorded	200		200		271
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	239		239		45
Unpaid Principal Balance With An Allowance Recorded	241		241		44
Related Allowance With An Allowance Recorded	44		44		18
Recorded Investment, Total	426		426		316
Unpaid Principal Balance, Total	441		441		315
Related Allowance, Total	44		44		$ 18
Average Recorded Investment With No Allowance Recorded	171	282	233	269
Interest Income Recognized With No Allowance Recorded	1	3	7	8
Average Recorded Investment With An Allowance Recorded	251	43	141	50
Interest Income Recognized With An Allowance Recorded	3	0	4	1
Average Recorded Investment, Total	422	325	374	319
Interest Income Recognized, Total	$ 4	$ 3	$ 11	$ 9

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-Name Accounting Standards Codification
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