Financing Activities (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Receivables [Abstract]
Period after which unpaid installments are considered as past due	30 days
Period after which collection of future income is considered as not probable	120 days
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	$ 286	$ 208
61-90 Days Past Due	121	91
91 Plus Days Past Due	501	403
Total Past Due	908	702
Current	27,501	28,773
Total gross finance receivables	28,409	29,475
91 Plus, Still Accruing	91	38
Investment in finance receivables on non-accrual status	598	468
North America
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	12,637	12,526
Europe
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	3,306	3,581
Asia/Pacific
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	3,669	3,931
Mining
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	1,992	2,126
Latin America
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	3,629	4,141
Caterpillar Power Finance
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	3,176	3,170
Customer
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	20,196	21,068
Customer | North America
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	37	46
61-90 Days Past Due	14	8
91 Plus Days Past Due	35	27
Total Past Due	86	81
Current	7,337	7,291
Total gross finance receivables	7,423	7,372
91 Plus, Still Accruing	9	4
Investment in finance receivables on non-accrual status	31	27
Customer | Europe
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	26	16
61-90 Days Past Due	15	23
91 Plus Days Past Due	43	29
Total Past Due	84	68
Current	2,335	2,607
Total gross finance receivables	2,419	2,675
91 Plus, Still Accruing	6	6
Investment in finance receivables on non-accrual status	43	28
Customer | Asia/Pacific
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	73	29
61-90 Days Past Due	32	22
91 Plus Days Past Due	64	69
Total Past Due	169	120
Current	2,518	2,773
Total gross finance receivables	2,687	2,893
91 Plus, Still Accruing	24	16
Investment in finance receivables on non-accrual status	44	54
Customer | Mining
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	20	28
61-90 Days Past Due	10	0
91 Plus Days Past Due	76	11
Total Past Due	106	39
Current	1,883	2,084
Total gross finance receivables	1,989	2,123
91 Plus, Still Accruing	50	0
Investment in finance receivables on non-accrual status	124	62
Customer | Latin America
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	100	55
61-90 Days Past Due	47	23
91 Plus Days Past Due	190	196
Total Past Due	337	274
Current	2,181	2,583
Total gross finance receivables	2,518	2,857
91 Plus, Still Accruing	0	8
Investment in finance receivables on non-accrual status	213	201
Customer | Caterpillar Power Finance
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	17	1
61-90 Days Past Due	1	4
91 Plus Days Past Due	87	64
Total Past Due	105	69
Current	3,055	3,079
Total gross finance receivables	3,160	3,148
91 Plus, Still Accruing	1	1
Investment in finance receivables on non-accrual status	143	96
Dealer
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	5,130	5,169
Investment in finance receivables on non-accrual status	0	0
Dealer | North America
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	0	0
61-90 Days Past Due	0	0
91 Plus Days Past Due	0	0
Total Past Due	0	0
Current	3,266	3,209
Total gross finance receivables	3,266	3,209
91 Plus, Still Accruing	0	0
Dealer | Europe
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	0	0
61-90 Days Past Due	0	0
91 Plus Days Past Due	0	0
Total Past Due	0	0
Current	463	467
Total gross finance receivables	463	467
91 Plus, Still Accruing	0	0
Dealer | Asia/Pacific
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	2	0
61-90 Days Past Due	0	0
91 Plus Days Past Due	0	0
Total Past Due	2	0
Current	596	637
Total gross finance receivables	598	637
91 Plus, Still Accruing	0	0
Dealer | Mining
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	0	0
61-90 Days Past Due	0	0
91 Plus Days Past Due	0	0
Total Past Due	0	0
Current	3	3
Total gross finance receivables	3	3
91 Plus, Still Accruing	0	0
Dealer | Latin America
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	0	0
61-90 Days Past Due	0	0
91 Plus Days Past Due	0	0
Total Past Due	0	0
Current	800	853
Total gross finance receivables	800	853
91 Plus, Still Accruing	0	0
Dealer | Caterpillar Power Finance
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	0	0
61-90 Days Past Due	0	0
91 Plus Days Past Due	0	0
Total Past Due	0	0
Current	0	0
Total gross finance receivables	0	0
91 Plus, Still Accruing	0	0
Caterpillar Purchased Receivables
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	3,083	3,238
Caterpillar Purchased Receivables | North America
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	8	23
61-90 Days Past Due	2	5
91 Plus Days Past Due	1	1
Total Past Due	11	29
Current	1,937	1,916
Total gross finance receivables	1,948	1,945
91 Plus, Still Accruing	1	1
Caterpillar Purchased Receivables | Europe
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	1	4
61-90 Days Past Due	0	1
91 Plus Days Past Due	5	5
Total Past Due	6	10
Current	418	429
Total gross finance receivables	424	439
91 Plus, Still Accruing	0	1
Investment in finance receivables on non-accrual status	5	4
Caterpillar Purchased Receivables | Asia/Pacific
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	0	0
61-90 Days Past Due	0	0
91 Plus Days Past Due	0	0
Total Past Due	0	0
Current	384	401
Total gross finance receivables	384	401
91 Plus, Still Accruing	0	0
Caterpillar Purchased Receivables | Mining
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	0	0
61-90 Days Past Due	0	0
91 Plus Days Past Due	0	0
Total Past Due	0	0
Current	0	0
Total gross finance receivables	0	0
91 Plus, Still Accruing	0	0
Caterpillar Purchased Receivables | Latin America
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	0	6
61-90 Days Past Due	0	5
91 Plus Days Past Due	0	0
Total Past Due	0	11
Current	311	420
Total gross finance receivables	311	431
91 Plus, Still Accruing	0	0
Caterpillar Purchased Receivables | Caterpillar Power Finance
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	2	0
61-90 Days Past Due	0	0
91 Plus Days Past Due	0	1
Total Past Due	2	1
Current	14	21
Total gross finance receivables	16	22
91 Plus, Still Accruing	$ 0	$ 1