Cat Financial Financing Activities (Details 3) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Dealer
Impaired finance receivables
Recorded Investment, Total	$ 0		$ 0		$ 0
Finance Receivables \| Customer
Impaired finance receivables
Recorded Investment With No Allowance Recorded	554		554		408
Unpaid Principal Balance With No Allowance Recorded	551		551		407
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	265		265		193
Unpaid Principal Balance With An Allowance Recorded	275		275		191
Related Allowance With An Allowance Recorded	85		85		65
Recorded Investment, Total	819		819		601
Unpaid Principal Balance, Total	826		826		598
Related Allowance, Total	85		85		65
Average Recorded Investment With No Allowance Recorded	504	$ 314	458	$ 326
Interest Income Recognized With No Allowance Recorded	6	2	13	7
Average Recorded Investment With An Allowance Recorded	216	269	197	286
Interest Income Recognized With An Allowance Recorded	1	3	5	8
Average Recorded Investment, Total	720	583	655	612
Interest Income Recognized, Total	7	5	18	15
Finance Receivables \| Customer \| North America
Impaired finance receivables
Recorded Investment With No Allowance Recorded	21		21		12
Unpaid Principal Balance With No Allowance Recorded	21		21		12
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	50		50		14
Unpaid Principal Balance With An Allowance Recorded	48		48		13
Related Allowance With An Allowance Recorded	19		19		4
Recorded Investment, Total	71		71		26
Unpaid Principal Balance, Total	69		69		25
Related Allowance, Total	19		19		4
Average Recorded Investment With No Allowance Recorded	24	10	19	12
Interest Income Recognized With No Allowance Recorded	0	1	1	1
Average Recorded Investment With An Allowance Recorded	42	10	28	7
Interest Income Recognized With An Allowance Recorded	0	0	0	0
Average Recorded Investment, Total	66	20	47	19
Interest Income Recognized, Total	0	1	1	1
Finance Receivables \| Customer \| Europe
Impaired finance receivables
Recorded Investment With No Allowance Recorded	49		49		41
Unpaid Principal Balance With No Allowance Recorded	48		48		41
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	9		9		11
Unpaid Principal Balance With An Allowance Recorded	9		9		10
Related Allowance With An Allowance Recorded	5		5		5
Recorded Investment, Total	58		58		52
Unpaid Principal Balance, Total	57		57		51
Related Allowance, Total	5		5		5
Average Recorded Investment With No Allowance Recorded	49	43	45	43
Interest Income Recognized With No Allowance Recorded	1	0	1	0
Average Recorded Investment With An Allowance Recorded	10	15	11	15
Interest Income Recognized With An Allowance Recorded	0	0	0	1
Average Recorded Investment, Total	59	58	56	58
Interest Income Recognized, Total	1	0	1	1
Finance Receivables \| Customer \| Asia Pacific
Impaired finance receivables
Recorded Investment With No Allowance Recorded	2		2		1
Unpaid Principal Balance With No Allowance Recorded	2		2		1
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	33		33		34
Unpaid Principal Balance With An Allowance Recorded	33		33		34
Related Allowance With An Allowance Recorded	5		5		4
Recorded Investment, Total	35		35		35
Unpaid Principal Balance, Total	35		35		35
Related Allowance, Total	5		5		4
Average Recorded Investment With No Allowance Recorded	1	1	2	2
Interest Income Recognized With No Allowance Recorded	0	0	0	0
Average Recorded Investment With An Allowance Recorded	35	41	34	33
Interest Income Recognized With An Allowance Recorded	0	0	2	1
Average Recorded Investment, Total	36	42	36	35
Interest Income Recognized, Total	0	0	2	1
Finance Receivables \| Customer \| Mining
Impaired finance receivables
Recorded Investment With No Allowance Recorded	119		119		84
Unpaid Principal Balance With No Allowance Recorded	118		118		84
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	38		38		11
Unpaid Principal Balance With An Allowance Recorded	38		38		11
Related Allowance With An Allowance Recorded	6		6		3
Recorded Investment, Total	157		157		95
Unpaid Principal Balance, Total	156		156		95
Related Allowance, Total	6		6		3
Average Recorded Investment With No Allowance Recorded	90	63	84	80
Interest Income Recognized With No Allowance Recorded	2	0	3	3
Average Recorded Investment With An Allowance Recorded	19	9	15	47
Interest Income Recognized With An Allowance Recorded	0	0	0	1
Average Recorded Investment, Total	109	72	99	127
Interest Income Recognized, Total	2	0	3	4
Finance Receivables \| Customer \| Latin America
Impaired finance receivables
Recorded Investment With No Allowance Recorded	73		73		28
Unpaid Principal Balance With No Allowance Recorded	73		73		28
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	91		91		53
Unpaid Principal Balance With An Allowance Recorded	103		103		53
Related Allowance With An Allowance Recorded	33		33		21
Recorded Investment, Total	164		164		81
Unpaid Principal Balance, Total	176		176		81
Related Allowance, Total	33		33		21
Average Recorded Investment With No Allowance Recorded	58	32	39	32
Interest Income Recognized With No Allowance Recorded	0	0	0	0
Average Recorded Investment With An Allowance Recorded	67	69	59	56
Interest Income Recognized With An Allowance Recorded	1	1	2	2
Average Recorded Investment, Total	125	101	98	88
Interest Income Recognized, Total	1	1	2	2
Finance Receivables \| Customer \| Caterpillar Power Finance
Impaired finance receivables
Recorded Investment With No Allowance Recorded	290		290		242
Unpaid Principal Balance With No Allowance Recorded	289		289		241
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	44		44		70
Unpaid Principal Balance With An Allowance Recorded	44		44		70
Related Allowance With An Allowance Recorded	17		17		28
Recorded Investment, Total	334		334		312
Unpaid Principal Balance, Total	333		333		311
Related Allowance, Total	17		17		$ 28
Average Recorded Investment With No Allowance Recorded	282	165	269	157
Interest Income Recognized With No Allowance Recorded	3	1	8	3
Average Recorded Investment With An Allowance Recorded	43	125	50	128
Interest Income Recognized With An Allowance Recorded	0	2	1	3
Average Recorded Investment, Total	325	290	319	285
Interest Income Recognized, Total	$ 3	$ 3	$ 9	$ 6

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