Cat Financial Financing Activities (Details 2) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Aging related to loans and finance leases
Finance receivables held-for-sale	$ 221
Finance Receivables
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	921	$ 805
Current	21,581	21,827
Total Finance Receivables	22,502	22,632
91+ Still Accruing	54	36
Finance Receivables | 31 to 60 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	214	165
Finance Receivables | 61 to 90 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	165	192
Finance Receivables | 91 Days of More Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	542	448
Finance Receivables | Customer
Aging related to loans and finance leases
Total Finance Receivables	19,135	19,168
Finance Receivables | Customer | North America
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	139	128
Current	7,934	7,950
Total Finance Receivables	8,073	8,078
91+ Still Accruing	6	8
Finance Receivables | Customer | North America | 31 to 60 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	73	71
Finance Receivables | Customer | North America | 61 to 90 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	28	15
Finance Receivables | Customer | North America | 91 Days of More Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	38	42
Finance Receivables | Customer | Europe
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	97	77
Current	2,759	2,718
Total Finance Receivables	2,856	2,795
91+ Still Accruing	10	13
Finance Receivables | Customer | Europe | 31 to 60 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	20	21
Finance Receivables | Customer | Europe | 61 to 90 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	23	10
Finance Receivables | Customer | Europe | 91 Days of More Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	54	46
Finance Receivables | Customer | Asia Pacific
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	47	34
Current	2,114	2,009
Total Finance Receivables	2,161	2,043
91+ Still Accruing	6	5
Finance Receivables | Customer | Asia Pacific | 31 to 60 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	23	13
Finance Receivables | Customer | Asia Pacific | 61 to 90 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	11	7
Finance Receivables | Customer | Asia Pacific | 91 Days of More Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	13	14
Finance Receivables | Customer | Mining
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	20	64
Current	1,755	1,751
Total Finance Receivables	1,775	1,815
91+ Still Accruing	1	9
Finance Receivables | Customer | Mining | 31 to 60 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	7	3
Finance Receivables | Customer | Mining | 61 to 90 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	1	1
Finance Receivables | Customer | Mining | 91 Days of More Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	12	60
Finance Receivables | Customer | Latin America
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	235	234
Current	1,460	1,531
Total Finance Receivables	1,695	1,765
91+ Still Accruing	3	0
Finance Receivables | Customer | Latin America | 31 to 60 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	49	37
Finance Receivables | Customer | Latin America | 61 to 90 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	43	55
Finance Receivables | Customer | Latin America | 91 Days of More Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	143	142
Finance Receivables | Customer | Caterpillar Power Finance
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	307	196
Current	2,268	2,476
Total Finance Receivables	2,575	2,672
91+ Still Accruing	28	1
Finance Receivables | Customer | Caterpillar Power Finance | 31 to 60 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	41	20
Finance Receivables | Customer | Caterpillar Power Finance | 61 to 90 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	57	32
Finance Receivables | Customer | Caterpillar Power Finance | 91 Days of More Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	209	144
Finance Receivables | Dealer
Aging related to loans and finance leases
Total Finance Receivables	3,367	3,464
Finance Receivables | Dealer | North America
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Current	1,937	1,920
Total Finance Receivables	1,937	1,920
91+ Still Accruing	0	0
Finance Receivables | Dealer | North America | 31 to 60 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Finance Receivables | Dealer | North America | 61 to 90 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Finance Receivables | Dealer | North America | 91 Days of More Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Finance Receivables | Dealer | Europe
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Current	191	222
Total Finance Receivables	191	222
91+ Still Accruing	0	0
Finance Receivables | Dealer | Europe | 31 to 60 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Finance Receivables | Dealer | Europe | 61 to 90 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Finance Receivables | Dealer | Europe | 91 Days of More Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Finance Receivables | Dealer | Asia Pacific
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Current	486	553
Total Finance Receivables	486	553
91+ Still Accruing	0	0
Finance Receivables | Dealer | Asia Pacific | 31 to 60 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Finance Receivables | Dealer | Asia Pacific | 61 to 90 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Finance Receivables | Dealer | Asia Pacific | 91 Days of More Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Finance Receivables | Dealer | Mining
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Current	4	4
Total Finance Receivables	4	4
91+ Still Accruing	0	0
Finance Receivables | Dealer | Mining | 31 to 60 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Finance Receivables | Dealer | Mining | 61 to 90 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Finance Receivables | Dealer | Mining | 91 Days of More Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Finance Receivables | Dealer | Latin America
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	76	72
Current	671	691
Total Finance Receivables	747	763
91+ Still Accruing	0	0
Finance Receivables | Dealer | Latin America | 31 to 60 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	1	0
Finance Receivables | Dealer | Latin America | 61 to 90 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	2	72
Finance Receivables | Dealer | Latin America | 91 Days of More Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	73	0
Finance Receivables | Dealer | Caterpillar Power Finance
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Current	2	2
Total Finance Receivables	2	2
91+ Still Accruing	0	0
Finance Receivables | Dealer | Caterpillar Power Finance | 31 to 60 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Finance Receivables | Dealer | Caterpillar Power Finance | 61 to 90 Days Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	0	0
Finance Receivables | Dealer | Caterpillar Power Finance | 91 Days of More Past Due
Aging related to loans and finance leases
Financing Receivable, Recorded Investment, Past Due	$ 0	$ 0