Cat Financial Financing Activities (Details 3) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Dealer
Impaired finance receivables
Recorded Investment, Total			$ 78
Dealer \| Latin America
Impaired finance receivables
Recorded Investment, Total	$ 78
Finance Receivables \| Customer
Impaired finance receivables
Recorded Investment With No Allowance Recorded	107		142
Unpaid Principal Balance With No Allowance Recorded	107		156
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	706		716
Unpaid Principal Balance With An Allowance Recorded	715		722
Related Allowance With An Allowance Recorded	302		288
Recorded Investment, Total	813		858
Unpaid Principal Balance, Total	822		878
Related Allowance, Total	302		288
Average Recorded Investment With No Allowance Recorded	126	$ 404
Interest Income Recognized With No Allowance Recorded	1	5
Average Recorded Investment With An Allowance Recorded	712	540
Interest Income Recognized With An Allowance Recorded	7	3
Average Recorded Investment, Total	838	944
Interest Income Recognized, Total	8	8
Finance Receivables \| Customer \| North America
Impaired finance receivables
Recorded Investment With No Allowance Recorded	9		10
Unpaid Principal Balance With No Allowance Recorded	9		10
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	41		40
Unpaid Principal Balance With An Allowance Recorded	38		41
Related Allowance With An Allowance Recorded	16		14
Recorded Investment, Total	50		50
Unpaid Principal Balance, Total	47		51
Related Allowance, Total	16		14
Average Recorded Investment With No Allowance Recorded	10	17
Interest Income Recognized With No Allowance Recorded	0	0
Average Recorded Investment With An Allowance Recorded	40	51
Interest Income Recognized With An Allowance Recorded	1	1
Average Recorded Investment, Total	50	68
Interest Income Recognized, Total	1	1
Finance Receivables \| Customer \| Europe
Impaired finance receivables
Recorded Investment With No Allowance Recorded	1		1
Unpaid Principal Balance With No Allowance Recorded	1		1
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	93		92
Unpaid Principal Balance With An Allowance Recorded	93		92
Related Allowance With An Allowance Recorded	57		57
Recorded Investment, Total	94		93
Unpaid Principal Balance, Total	94		93
Related Allowance, Total	57		57
Average Recorded Investment With No Allowance Recorded	1	36
Interest Income Recognized With No Allowance Recorded	0	0
Average Recorded Investment With An Allowance Recorded	94	19
Interest Income Recognized With An Allowance Recorded	1	0
Average Recorded Investment, Total	95	55
Interest Income Recognized, Total	1	0
Finance Receivables \| Customer \| Asia Pacific
Impaired finance receivables
Recorded Investment With No Allowance Recorded	0		0
Unpaid Principal Balance With No Allowance Recorded	0		0
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	9		4
Unpaid Principal Balance With An Allowance Recorded	9		4
Related Allowance With An Allowance Recorded	3		2
Recorded Investment, Total	9		4
Unpaid Principal Balance, Total	9		4
Related Allowance, Total	3		2
Average Recorded Investment With No Allowance Recorded	0	31
Interest Income Recognized With No Allowance Recorded	0	1
Average Recorded Investment With An Allowance Recorded	7	6
Interest Income Recognized With An Allowance Recorded	0	0
Average Recorded Investment, Total	7	37
Interest Income Recognized, Total	0	1
Finance Receivables \| Customer \| Mining
Impaired finance receivables
Recorded Investment With No Allowance Recorded	29		33
Unpaid Principal Balance With No Allowance Recorded	29		33
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	32		56
Unpaid Principal Balance With An Allowance Recorded	31		55
Related Allowance With An Allowance Recorded	14		26
Recorded Investment, Total	61		89
Unpaid Principal Balance, Total	60		88
Related Allowance, Total	14		26
Average Recorded Investment With No Allowance Recorded	31	103
Interest Income Recognized With No Allowance Recorded	0	1
Average Recorded Investment With An Allowance Recorded	43	17
Interest Income Recognized With An Allowance Recorded	1	0
Average Recorded Investment, Total	74	120
Interest Income Recognized, Total	1	1
Finance Receivables \| Customer \| Latin America
Impaired finance receivables
Recorded Investment With No Allowance Recorded	20		29
Unpaid Principal Balance With No Allowance Recorded	20		29
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	76		75
Unpaid Principal Balance With An Allowance Recorded	76		75
Related Allowance With An Allowance Recorded	27		25
Recorded Investment, Total	96		104
Unpaid Principal Balance, Total	96		104
Related Allowance, Total	27		25
Average Recorded Investment With No Allowance Recorded	24	45
Interest Income Recognized With No Allowance Recorded	0	1
Average Recorded Investment With An Allowance Recorded	77	87
Interest Income Recognized With An Allowance Recorded	1	1
Average Recorded Investment, Total	101	132
Interest Income Recognized, Total	1	2
Finance Receivables \| Customer \| Caterpillar Power Finance
Impaired finance receivables
Recorded Investment With No Allowance Recorded	48		69
Unpaid Principal Balance With No Allowance Recorded	48		83
Related Allowance With No Allowance Recorded	0		0
Recorded Investment With An Allowance Recorded	455		449
Unpaid Principal Balance With An Allowance Recorded	468		455
Related Allowance With An Allowance Recorded	185		164
Recorded Investment, Total	503		518
Unpaid Principal Balance, Total	516		538
Related Allowance, Total	185		164
Average Recorded Investment With No Allowance Recorded	60	172
Interest Income Recognized With No Allowance Recorded	1	2
Average Recorded Investment With An Allowance Recorded	451	360
Interest Income Recognized With An Allowance Recorded	3	1
Average Recorded Investment, Total	511	532
Interest Income Recognized, Total	4	$ 3
Finance Receivables \| Dealer \| Latin America
Impaired finance receivables
Related Allowance With An Allowance Recorded	27		14
Related Allowance, Total	$ 27		$ 14

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