Cat Financial Financing Activities (Details 3) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 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	446		446		530
Unpaid Principal Balance With No Allowance Recorded	448		448		528
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	452		452		256
Unpaid Principal Balance With An Allowance Recorded	461		461		265
Related Allowance With An Allowance Recorded	113		113		85
Recorded Investment, Total	898		898		786
Unpaid Principal Balance, Total	909		909		793
Related Allowance, Total	113		113		85
Average Recorded Investment With No Allowance Recorded	543	$ 453	534	$ 435
Interest Income Recognized With No Allowance Recorded	8	3	13	7
Average Recorded Investment With An Allowance Recorded	319	188	297	186
Interest Income Recognized With An Allowance Recorded	2	2	5	4
Average Recorded Investment, Total	862	641	831	621
Interest Income Recognized, Total	10	5	18	11
Finance Receivables \| Customer \| North America
Impaired finance receivables
Recorded Investment With No Allowance Recorded	13		13		10
Unpaid Principal Balance With No Allowance Recorded	13		13		10
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	49		49		61
Unpaid Principal Balance With An Allowance Recorded	48		48		60
Related Allowance With An Allowance Recorded	20		20		22
Recorded Investment, Total	62		62		71
Unpaid Principal Balance, Total	61		61		70
Related Allowance, Total	20		20		22
Average Recorded Investment With No Allowance Recorded	11	24	11	19
Interest Income Recognized With No Allowance Recorded	0	1	0	1
Average Recorded Investment With An Allowance Recorded	52	25	56	20
Interest Income Recognized With An Allowance Recorded	1	0	1	0
Average Recorded Investment, Total	63	49	67	39
Interest Income Recognized, Total	1	1	1	1
Finance Receivables \| Customer \| Europe
Impaired finance receivables
Recorded Investment With No Allowance Recorded	48		48		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	4		4		7
Unpaid Principal Balance With An Allowance Recorded	4		4		7
Related Allowance With An Allowance Recorded	2		2		3
Recorded Investment, Total	52		52		56
Unpaid Principal Balance, Total	51		51		55
Related Allowance, Total	2		2		3
Average Recorded Investment With No Allowance Recorded	48	44	48	43
Interest Income Recognized With No Allowance Recorded	1	0	1	0
Average Recorded Investment With An Allowance Recorded	5	12	6	12
Interest Income Recognized With An Allowance Recorded	0	0	0	0
Average Recorded Investment, Total	53	56	54	55
Interest Income Recognized, Total	1	0	1	0
Finance Receivables \| Customer \| Asia Pacific
Impaired finance receivables
Recorded Investment With No Allowance Recorded	29		29		3
Unpaid Principal Balance With No Allowance Recorded	29		29		2
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	29		29		50
Unpaid Principal Balance With An Allowance Recorded	29		29		50
Related Allowance With An Allowance Recorded	3		3		8
Recorded Investment, Total	58		58		53
Unpaid Principal Balance, Total	58		58		52
Related Allowance, Total	3		3		8
Average Recorded Investment With No Allowance Recorded	30	3	18	2
Interest Income Recognized With No Allowance Recorded	1	0	1	0
Average Recorded Investment With An Allowance Recorded	30	36	38	35
Interest Income Recognized With An Allowance Recorded	0	1	1	2
Average Recorded Investment, Total	60	39	56	37
Interest Income Recognized, Total	1	1	2	2
Finance Receivables \| Customer \| Mining
Impaired finance receivables
Recorded Investment With No Allowance Recorded	130		130		129
Unpaid Principal Balance With No Allowance Recorded	130		130		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	130		130		129
Unpaid Principal Balance, Total	130		130		129
Related Allowance, Total	0		0		0
Average Recorded Investment With No Allowance Recorded	130	80	129	80
Interest Income Recognized With No Allowance Recorded	3	0	4	1
Average Recorded Investment With An Allowance Recorded	0	13	0	12
Interest Income Recognized With An Allowance Recorded	0	0	0	0
Average Recorded Investment, Total	130	93	129	92
Interest Income Recognized, Total	3	0	4	1
Finance Receivables \| Customer \| Latin America
Impaired finance receivables
Recorded Investment With No Allowance Recorded	68		68		68
Unpaid Principal Balance With No Allowance Recorded	67		67		68
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	107		107		93
Unpaid Principal Balance With An Allowance Recorded	119		119		104
Related Allowance With An Allowance Recorded	43		43		34
Recorded Investment, Total	175		175		161
Unpaid Principal Balance, Total	186		186		172
Related Allowance, Total	43		43		34
Average Recorded Investment With No Allowance Recorded	67	29	70	29
Interest Income Recognized With No Allowance Recorded	0	0	1	0
Average Recorded Investment With An Allowance Recorded	107	57	101	54
Interest Income Recognized With An Allowance Recorded	1	0	2	1
Average Recorded Investment, Total	174	86	171	83
Interest Income Recognized, Total	1	0	3	1
Finance Receivables \| Customer \| Caterpillar Power Finance
Impaired finance receivables
Recorded Investment With No Allowance Recorded	158		158		271
Unpaid Principal Balance With No Allowance Recorded	162		162		271
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	263		263		45
Unpaid Principal Balance With An Allowance Recorded	261		261		44
Related Allowance With An Allowance Recorded	45		45		18
Recorded Investment, Total	421		421		316
Unpaid Principal Balance, Total	423		423		315
Related Allowance, Total	45		45		$ 18
Average Recorded Investment With No Allowance Recorded	257	273	258	262
Interest Income Recognized With No Allowance Recorded	3	2	6	5
Average Recorded Investment With An Allowance Recorded	125	45	96	53
Interest Income Recognized With An Allowance Recorded	0	1	1	1
Average Recorded Investment, Total	382	318	354	315
Interest Income Recognized, Total	$ 3	$ 3	$ 7	$ 6

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