Financing Activities (Details 2) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2012 D	Dec. 31, 2011
Financing Activities [Abstract]
Period after which unpaid installments are considered as past due	30
Period after which collection of future income is considered as not probable	120
Financing Receivable, Recorded Investment, Past Due [Abstract]
31-60 Days Past Due	$ 306	$ 224
61-90 Days Past Due	132	108
Greater than 91 Days Past Due	534	450
Total Past Due	972	782
Current	25,744	24,343
Total Finance Receivables	26,716	25,125
Greater than 91, Still Accruing	41	66
Investment in loans and finance leases on non-accrual status	648	472
North America
Financing Receivable, Recorded Investment, Past Due [Abstract]
Total Finance Receivables	9,953	9,923
Europe
Financing Receivable, Recorded Investment, Past Due [Abstract]
Total Finance Receivables	3,128	2,960
Asia/Pacific
Financing Receivable, Recorded Investment, Past Due [Abstract]
Total Finance Receivables	4,771	4,192
Mining
Financing Receivable, Recorded Investment, Past Due [Abstract]
Total Finance Receivables	1,725	1,485
Latin America
Financing Receivable, Recorded Investment, Past Due [Abstract]
Total Finance Receivables	3,943	3,616
Caterpillar Power Finance
Financing Receivable, Recorded Investment, Past Due [Abstract]
Total Finance Receivables	3,196	2,949
Customer
Financing Receivable, Recorded Investment, Past Due [Abstract]
Total Finance Receivables	18,871	17,998
Customer | North America
Financing Receivable, Recorded Investment, Past Due [Abstract]
31-60 Days Past Due	41	75
61-90 Days Past Due	17	39
Greater than 91 Days Past Due	89	111
Total Past Due	147	225
Current	5,572	5,448
Total Finance Receivables	5,719	5,673
Greater than 91, Still Accruing	1	9
Investment in loans and finance leases on non-accrual status	92	112
Customer | Europe
Financing Receivable, Recorded Investment, Past Due [Abstract]
31-60 Days Past Due	32	27
61-90 Days Past Due	27	11
Greater than 91 Days Past Due	56	57
Total Past Due	115	95
Current	2,204	2,129
Total Finance Receivables	2,319	2,224
Greater than 91, Still Accruing	10	10
Investment in loans and finance leases on non-accrual status	48	58
Customer | Asia/Pacific
Financing Receivable, Recorded Investment, Past Due [Abstract]
31-60 Days Past Due	82	48
61-90 Days Past Due	29	23
Greater than 91 Days Past Due	42	38
Total Past Due	153	109
Current	3,209	3,102
Total Finance Receivables	3,362	3,211
Greater than 91, Still Accruing	15	14
Investment in loans and finance leases on non-accrual status	30	24
Customer | Mining
Financing Receivable, Recorded Investment, Past Due [Abstract]
31-60 Days Past Due	4	0
61-90 Days Past Due	0	0
Greater than 91 Days Past Due	12	12
Total Past Due	16	12
Current	1,708	1,473
Total Finance Receivables	1,724	1,485
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 [Abstract]
31-60 Days Past Due	45	32
61-90 Days Past Due	23	15
Greater than 91 Days Past Due	157	99
Total Past Due	225	146
Current	2,354	2,339
Total Finance Receivables	2,579	2,485
Greater than 91, Still Accruing	0	0
Investment in loans and finance leases on non-accrual status	169	108
Customer | Caterpillar Power Finance
Financing Receivable, Recorded Investment, Past Due [Abstract]
31-60 Days Past Due	83	14
61-90 Days Past Due	32	16
Greater than 91 Days Past Due	177	125
Total Past Due	292	155
Current	2,876	2,765
Total Finance Receivables	3,168	2,920
Greater than 91, Still Accruing	14	25
Investment in loans and finance leases on non-accrual status	297	158
Dealer
Financing Receivable, Recorded Investment, Past Due [Abstract]
Total Finance Receivables	4,719	3,973
Investment in loans and finance leases on non-accrual status	0	0
Dealer | North America
Financing Receivable, Recorded Investment, Past Due [Abstract]
31-60 Days Past Due	0	0
61-90 Days Past Due	0	0
Greater than 91 Days Past Due	0	2
Total Past Due	0	2
Current	2,411	2,412
Total Finance Receivables	2,411	2,414
Greater than 91, Still Accruing	0	2
Dealer | Europe
Financing Receivable, Recorded Investment, Past Due [Abstract]
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	425	334
Total Finance Receivables	425	334
Greater than 91, Still Accruing	0	0
Dealer | Asia/Pacific
Financing Receivable, Recorded Investment, Past Due [Abstract]
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	991	516
Total Finance Receivables	991	516
Greater than 91, Still Accruing	0	0
Dealer | Mining
Financing Receivable, Recorded Investment, Past Due [Abstract]
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	0
Total Finance Receivables	1	0
Greater than 91, Still Accruing	0	0
Dealer | Latin America
Financing Receivable, Recorded Investment, Past Due [Abstract]
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	891	709
Total Finance Receivables	891	709
Greater than 91, Still Accruing	0	0
Dealer | Caterpillar Power Finance
Financing Receivable, Recorded Investment, Past Due [Abstract]
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 Finance Receivables	0	0
Greater than 91, Still Accruing	0	0
Caterpillar Purchased Receivables
Financing Receivable, Recorded Investment, Past Due [Abstract]
Total Finance Receivables	3,126	3,154
Investment in loans and finance leases on non-accrual status	0	0
Caterpillar Purchased Receivables | North America
Financing Receivable, Recorded Investment, Past Due [Abstract]
31-60 Days Past Due	16	25
61-90 Days Past Due	4	4
Greater than 91 Days Past Due	1	6
Total Past Due	21	35
Current	1,802	1,801
Total Finance Receivables	1,823	1,836
Greater than 91, Still Accruing	1	6
Caterpillar Purchased Receivables | Europe
Financing Receivable, Recorded Investment, Past Due [Abstract]
31-60 Days Past Due	1	3
61-90 Days Past Due	0	0
Greater than 91 Days Past Due	0	0
Total Past Due	1	3
Current	383	399
Total Finance Receivables	384	402
Greater than 91, Still Accruing	0	0
Caterpillar Purchased Receivables | Asia/Pacific
Financing Receivable, Recorded Investment, Past Due [Abstract]
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	418	465
Total Finance Receivables	418	465
Greater than 91, Still Accruing	0	0
Caterpillar Purchased Receivables | Mining
Financing Receivable, Recorded Investment, Past Due [Abstract]
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 Finance Receivables	0	0
Greater than 91, Still Accruing	0	0
Caterpillar Purchased Receivables | Latin America
Financing Receivable, Recorded Investment, Past Due [Abstract]
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	473	422
Total Finance Receivables	473	422
Greater than 91, Still Accruing	0	0
Caterpillar Purchased Receivables | Caterpillar Power Finance
Financing Receivable, Recorded Investment, Past Due [Abstract]
31-60 Days Past Due	2	0
61-90 Days Past Due	0	0
Greater than 91 Days Past Due	0	0
Total Past Due	2	0
Current	26	29
Total Finance Receivables	28	29
Greater than 91, Still Accruing	$ 0	$ 0