Cat Financial Financing Activities (Details 3) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Dealer
Impaired finance receivables
Recorded Investment, Total	$ 0		$ 0		$ 0
Finance Receivables \| Customer
Impaired finance receivables
Recorded Investment With No Allowance Recorded	272		272		424
Unpaid Principal Balance With No Allowance Recorded	292		292		435
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	555		555		518
Unpaid Principal Balance With An Allowance Recorded	554		554		530
Related Allowance With An Allowance Recorded	205		205		149
Recorded Investment, Total	827		827		942
Unpaid Principal Balance, Total	846		846		965
Related Allowance, Total	205		205		149
Average Recorded Investment With No Allowance Recorded	330	$ 543	371	$ 534
Interest Income Recognized With No Allowance Recorded	3	8	8	13
Average Recorded Investment With An Allowance Recorded	594	319	557	297
Interest Income Recognized With An Allowance Recorded	6	2	9	5
Average Recorded Investment, Total	924	862	928	831
Interest Income Recognized, Total	9	10	17	18
Finance Receivables \| Customer \| North America
Impaired finance receivables
Recorded Investment With No Allowance Recorded	20		20		19
Unpaid Principal Balance With No Allowance Recorded	20		20		19
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	49		49		44
Unpaid Principal Balance With An Allowance Recorded	47		47		43
Related Allowance With An Allowance Recorded	23		23		17
Recorded Investment, Total	69		69		63
Unpaid Principal Balance, Total	67		67		62
Related Allowance, Total	23		23		17
Average Recorded Investment With No Allowance Recorded	18	11	18	11
Interest Income Recognized With No Allowance Recorded	1	0	1	0
Average Recorded Investment With An Allowance Recorded	56	52	53	56
Interest Income Recognized With An Allowance Recorded	0	1	1	1
Average Recorded Investment, Total	74	63	71	67
Interest Income Recognized, Total	1	1	2	1
Finance Receivables \| Customer \| Europe
Impaired finance receivables
Recorded Investment With No Allowance Recorded	6		6		45
Unpaid Principal Balance With No Allowance Recorded	6		6		45
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	48		48		9
Unpaid Principal Balance With An Allowance Recorded	47		47		8
Related Allowance With An Allowance Recorded	24		24		5
Recorded Investment, Total	54		54		54
Unpaid Principal Balance, Total	53		53		53
Related Allowance, Total	24		24		5
Average Recorded Investment With No Allowance Recorded	7	48	23	48
Interest Income Recognized With No Allowance Recorded	0	1	0	1
Average Recorded Investment With An Allowance Recorded	48	5	32	6
Interest Income Recognized With An Allowance Recorded	1	0	1	0
Average Recorded Investment, Total	55	53	55	54
Interest Income Recognized, Total	1	1	1	1
Finance Receivables \| Customer \| Asia Pacific
Impaired finance receivables
Recorded Investment With No Allowance Recorded	29		29		34
Unpaid Principal Balance With No Allowance Recorded	29		29		33
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	3		3		8
Unpaid Principal Balance With An Allowance Recorded	3		3		8
Related Allowance With An Allowance Recorded	1		1		2
Recorded Investment, Total	32		32		42
Unpaid Principal Balance, Total	32		32		41
Related Allowance, Total	1		1		2
Average Recorded Investment With No Allowance Recorded	28	30	30	18
Interest Income Recognized With No Allowance Recorded	0	1	1	1
Average Recorded Investment With An Allowance Recorded	5	30	5	38
Interest Income Recognized With An Allowance Recorded	0	0	0	1
Average Recorded Investment, Total	33	60	35	56
Interest Income Recognized, Total	0	1	1	2
Finance Receivables \| Customer \| Mining
Impaired finance receivables
Recorded Investment With No Allowance Recorded	38		38		121
Unpaid Principal Balance With No Allowance Recorded	38		38		121
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	62		62		0
Unpaid Principal Balance With An Allowance Recorded	62		62		0
Related Allowance With An Allowance Recorded	21		21		0
Recorded Investment, Total	100		100		121
Unpaid Principal Balance, Total	100		100		121
Related Allowance, Total	21		21		0
Average Recorded Investment With No Allowance Recorded	45	130	78	129
Interest Income Recognized With No Allowance Recorded	1	3	2	4
Average Recorded Investment With An Allowance Recorded	64	0	36	0
Interest Income Recognized With An Allowance Recorded	1	0	1	0
Average Recorded Investment, Total	109	130	114	129
Interest Income Recognized, Total	2	3	3	4
Finance Receivables \| Customer \| Latin America
Impaired finance receivables
Recorded Investment With No Allowance Recorded	40		40		45
Unpaid Principal Balance With No Allowance Recorded	40		40		45
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	50		50		95
Unpaid Principal Balance With An Allowance Recorded	50		50		106
Related Allowance With An Allowance Recorded	37		37		42
Recorded Investment, Total	90		90		140
Unpaid Principal Balance, Total	90		90		151
Related Allowance, Total	37		37		42
Average Recorded Investment With No Allowance Recorded	43	67	44	70
Interest Income Recognized With No Allowance Recorded	0	0	1	1
Average Recorded Investment With An Allowance Recorded	65	107	76	101
Interest Income Recognized With An Allowance Recorded	1	1	2	2
Average Recorded Investment, Total	108	174	120	171
Interest Income Recognized, Total	1	1	3	3
Finance Receivables \| Customer \| Caterpillar Power Finance
Impaired finance receivables
Recorded Investment With No Allowance Recorded	139		139		160
Unpaid Principal Balance With No Allowance Recorded	159		159		172
Related Allowance With No Allowance Recorded	0		0		0
Recorded Investment With An Allowance Recorded	343		343		362
Unpaid Principal Balance With An Allowance Recorded	345		345		365
Related Allowance With An Allowance Recorded	99		99		83
Recorded Investment, Total	482		482		522
Unpaid Principal Balance, Total	504		504		537
Related Allowance, Total	99		99		$ 83
Average Recorded Investment With No Allowance Recorded	189	257	178	258
Interest Income Recognized With No Allowance Recorded	1	3	3	6
Average Recorded Investment With An Allowance Recorded	356	125	355	96
Interest Income Recognized With An Allowance Recorded	3	0	4	1
Average Recorded Investment, Total	545	382	533	354
Interest Income Recognized, Total	$ 4	$ 3	$ 7	$ 7

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-Name Accounting Standards Codification
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