Financing Activities (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
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	$ 241	$ 206
61-90 Days Past Due	118	73
Greater than 91 Days Past Due	422	421
Total Past Due	781	700
Current	27,999	27,883
Total gross finance receivables	28,780	28,583
Greater than 91, Still Accruing	40	31
Investment in loans and finance leases on non-accrual status	517	513
North America
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	10,282	10,271
Europe
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	3,639	3,539
Asia/Pacific
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	5,177	5,293
Mining
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	2,120	1,974
Latin America
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	4,339	4,323
Caterpillar Power Finance
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	3,223	3,183
Customer
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	20,121	19,883
Customer | North America
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	27	35
61-90 Days Past Due	7	8
Greater than 91 Days Past Due	43	52
Total Past Due	77	95
Current	5,921	5,889
Total gross finance receivables	5,998	5,984
Greater than 91, Still Accruing	1	0
Investment in loans and finance leases on non-accrual status	48	59
Customer | Europe
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	33	23
61-90 Days Past Due	16	9
Greater than 91 Days Past Due	41	36
Total Past Due	90	68
Current	2,411	2,487
Total gross finance receivables	2,501	2,555
Greater than 91, Still Accruing	6	6
Investment in loans and finance leases on non-accrual status	41	38
Customer | Asia/Pacific
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	62	53
61-90 Days Past Due	34	19
Greater than 91 Days Past Due	81	54
Total Past Due	177	126
Current	3,256	3,354
Total gross finance receivables	3,433	3,480
Greater than 91, Still Accruing	30	18
Investment in loans and finance leases on non-accrual status	53	36
Customer | Mining
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	5	0
61-90 Days Past Due	0	1
Greater than 91 Days Past Due	12	12
Total Past Due	17	13
Current	2,102	1,960
Total gross finance receivables	2,119	1,973
Greater than 91, Still Accruing	0	0
Investment in loans and finance leases on non-accrual status	12	12
Customer | Latin America
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	87	62
61-90 Days Past Due	26	19
Greater than 91 Days Past Due	152	138
Total Past Due	265	219
Current	2,592	2,500
Total gross finance receivables	2,857	2,719
Greater than 91, Still Accruing	0	0
Investment in loans and finance leases on non-accrual status	167	148
Customer | Caterpillar Power Finance
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	8	15
61-90 Days Past Due	31	14
Greater than 91 Days Past Due	92	126
Total Past Due	131	155
Current	3,082	3,017
Total gross finance receivables	3,213	3,172
Greater than 91, Still Accruing	2	4
Investment in loans and finance leases on non-accrual status	196	220
Dealer
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	5,493	5,586
Investment in loans and finance leases 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
Greater than 91 Days Past Due	0	0
Total Past Due	0	0
Current	2,776	2,931
Total gross finance receivables	2,776	2,931
Greater than 91, 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
Greater than 91 Days Past Due	0	0
Total Past Due	0	0
Current	684	652
Total gross finance receivables	684	652
Greater than 91, Still Accruing	0	0
Dealer | Asia/Pacific
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	0	0
61-90 Days Past Due	0	0
Greater than 91 Days Past Due	0	0
Total Past Due	0	0
Current	983	945
Total gross finance receivables	983	945
Greater than 91, 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
Greater than 91 Days Past Due	0	0
Total Past Due	0	0
Current	1	1
Total gross finance receivables	1	1
Greater than 91, 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
Greater than 91 Days Past Due	0	0
Total Past Due	0	0
Current	1,049	1,057
Total gross finance receivables	1,049	1,057
Greater than 91, 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
Greater than 91 Days Past Due	0	0
Total Past Due	0	0
Current	0	0
Total gross finance receivables	0	0
Greater than 91, Still Accruing	0	0
Caterpillar Purchased Receivables
Financing Receivable, Recorded Investment, Past Due
Total gross finance receivables	3,166	3,114
Investment in loans and finance leases on non-accrual status	0	0
Caterpillar Purchased Receivables | North America
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	17	17
61-90 Days Past Due	3	3
Greater than 91 Days Past Due	1	2
Total Past Due	21	22
Current	1,487	1,334
Total gross finance receivables	1,508	1,356
Greater than 91, Still Accruing	1	2
Caterpillar Purchased Receivables | Europe
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	2	1
61-90 Days Past Due	0	0
Greater than 91 Days Past Due	0	0
Total Past Due	2	1
Current	452	331
Total gross finance receivables	454	332
Greater than 91, Still Accruing	0	0
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
Greater than 91 Days Past Due	0	0
Total Past Due	0	0
Current	761	868
Total gross finance receivables	761	868
Greater than 91, 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
Greater than 91 Days Past Due	0	0
Total Past Due	0	0
Current	0	0
Total gross finance receivables	0	0
Greater than 91, Still Accruing	0	0
Caterpillar Purchased Receivables | Latin America
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	0	0
61-90 Days Past Due	0	0
Greater than 91 Days Past Due	0	0
Total Past Due	0	0
Current	433	547
Total gross finance receivables	433	547
Greater than 91, Still Accruing	0	0
Caterpillar Purchased Receivables | Caterpillar Power Finance
Financing Receivable, Recorded Investment, Past Due
31-60 Days Past Due	0	0
61-90 Days Past Due	1	0
Greater than 91 Days Past Due	0	1
Total Past Due	1	1
Current	9	10
Total gross finance receivables	10	11
Greater than 91, Still Accruing	$ 0	$ 1