Cat Financial Financing Activities (Details 3) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Dealer \| Latin America
Impaired finance receivables
Recorded Investment, Total					$ 78
Finance Receivables \| Customer
Impaired finance receivables
Recorded Investment With No Allowance Recorded	$ 128		$ 128		142
Unpaid Principal Balance With No Allowance Recorded	170		170		156
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	537		537		716
Unpaid Principal Balance With An Allowance Recorded	545		545		722
Related Allowance With An Allowance Recorded	182		182		288
Recorded Investment, Total	665		665		858
Unpaid Principal Balance, Total	715		715		878
Related Allowance, Total	182		182		288
Average Recorded Investment With No Allowance Recorded	130	$ 218	121	$ 319
Interest Income Recognized With No Allowance Recorded	1	4	4	12
Average Recorded Investment With An Allowance Recorded	632	593	677	572
Interest Income Recognized With An Allowance Recorded	5	6	18	15
Average Recorded Investment, Total	762	811	798	891
Interest Income Recognized, Total	6	10	22	27
Finance Receivables \| Customer \| North America
Impaired finance receivables
Recorded Investment With No Allowance Recorded	9		9		10
Unpaid Principal Balance With No Allowance Recorded	9		9		10
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	31		31		40
Unpaid Principal Balance With An Allowance Recorded	30		30		41
Related Allowance With An Allowance Recorded	9		9		14
Recorded Investment, Total	40		40		50
Unpaid Principal Balance, Total	39		39		51
Related Allowance, Total	9		9		14
Average Recorded Investment With No Allowance Recorded	10	19	10	17
Interest Income Recognized With No Allowance Recorded	0	0	0	1
Average Recorded Investment With An Allowance Recorded	30	47	36	51
Interest Income Recognized With An Allowance Recorded	0	0	1	1
Average Recorded Investment, Total	40	66	46	68
Interest Income Recognized, Total	0	0	1	2
Finance Receivables \| Customer \| EAME
Impaired finance receivables
Recorded Investment With No Allowance Recorded	0		0		1
Unpaid Principal Balance With No Allowance Recorded	0		0		1
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	60		60		92
Unpaid Principal Balance With An Allowance Recorded	60		60		92
Related Allowance With An Allowance Recorded	27		27		57
Recorded Investment, Total	60		60		93
Unpaid Principal Balance, Total	60		60		93
Related Allowance, Total	27		27		57
Average Recorded Investment With No Allowance Recorded	15	4	7	17
Interest Income Recognized With No Allowance Recorded	0	0	0	0
Average Recorded Investment With An Allowance Recorded	80	59	88	41
Interest Income Recognized With An Allowance Recorded	1	0	2	1
Average Recorded Investment, Total	95	63	95	58
Interest Income Recognized, Total	1	0	2	1
Finance Receivables \| Customer \| Asia Pacific
Impaired finance receivables
Recorded Investment With No Allowance Recorded	0		0		0
Unpaid Principal Balance With No Allowance Recorded	0		0		0
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	10		10		4
Unpaid Principal Balance With An Allowance Recorded	10		10		4
Related Allowance With An Allowance Recorded	4		4		2
Recorded Investment, Total	10		10		4
Unpaid Principal Balance, Total	10		10		4
Related Allowance, Total	4		4		2
Average Recorded Investment With No Allowance Recorded	0	29	0	30
Interest Income Recognized With No Allowance Recorded	0	1	0	2
Average Recorded Investment With An Allowance Recorded	12	2	9	4
Interest Income Recognized With An Allowance Recorded	1	0	1	0
Average Recorded Investment, Total	12	31	9	34
Interest Income Recognized, Total	1	1	1	2
Finance Receivables \| Customer \| Mining
Impaired finance receivables
Recorded Investment With No Allowance Recorded	23		23		33
Unpaid Principal Balance With No Allowance Recorded	23		23		33
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	61		61		56
Unpaid Principal Balance With An Allowance Recorded	59		59		55
Related Allowance With An Allowance Recorded	18		18		26
Recorded Investment, Total	84		84		89
Unpaid Principal Balance, Total	82		82		88
Related Allowance, Total	18		18		26
Average Recorded Investment With No Allowance Recorded	26	35	29	65
Interest Income Recognized With No Allowance Recorded	0	0	1	2
Average Recorded Investment With An Allowance Recorded	65	60	49	43
Interest Income Recognized With An Allowance Recorded	1	1	2	2
Average Recorded Investment, Total	91	95	78	108
Interest Income Recognized, Total	1	1	3	4
Finance Receivables \| Customer \| Latin America
Impaired finance receivables
Recorded Investment With No Allowance Recorded	25		25		29
Unpaid Principal Balance With No Allowance Recorded	25		25		29
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	66		66		75
Unpaid Principal Balance With An Allowance Recorded	64		64		75
Related Allowance With An Allowance Recorded	22		22		25
Recorded Investment, Total	91		91		104
Unpaid Principal Balance, Total	89		89		104
Related Allowance, Total	22		22		25
Average Recorded Investment With No Allowance Recorded	22	37	22	41
Interest Income Recognized With No Allowance Recorded	0	1	1	2
Average Recorded Investment With An Allowance Recorded	69	51	73	69
Interest Income Recognized With An Allowance Recorded	1	1	4	3
Average Recorded Investment, Total	91	88	95	110
Interest Income Recognized, Total	1	2	5	5
Finance Receivables \| Customer \| Caterpillar Power Finance
Impaired finance receivables
Recorded Investment With No Allowance Recorded	71		71		69
Unpaid Principal Balance With No Allowance Recorded	113		113		83
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	309		309		449
Unpaid Principal Balance With An Allowance Recorded	322		322		455
Related Allowance With An Allowance Recorded	102		102		164
Recorded Investment, Total	380		380		518
Unpaid Principal Balance, Total	435		435		538
Related Allowance, Total	102		102		164
Average Recorded Investment With No Allowance Recorded	57	94	53	149
Interest Income Recognized With No Allowance Recorded	1	2	2	5
Average Recorded Investment With An Allowance Recorded	376	374	422	364
Interest Income Recognized With An Allowance Recorded	1	4	8	8
Average Recorded Investment, Total	433	468	475	513
Interest Income Recognized, Total	2	$ 6	10	$ 13
Finance Receivables \| Dealer \| Latin America
Impaired finance receivables
Related Allowance With An Allowance Recorded	39		39		14
Recorded Investment, Total	78		78
Related Allowance, Total	$ 39		$ 39		$ 14

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