Financing Activities (Details 3) (USD $) In Millions, unless otherwise specified	6 Months Ended	12 Months Ended
	Jun. 30, 2012	Dec. 31, 2011
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	$ 369	$ 363
Receivables written off	(50)	(210)
Recoveries on receivables previously written off	23	52
Provision for credit losses	53	170
Adjustment due to sale of receivables	(1)	(3)
Foreign currency translation adjustment	(1)	(3)
Balance at end of period	393	369
Allowance, Ending Balance - Individually evaluated for impairment	61	56
Allowance, Ending Balance - Collectively evaluated for impairment	332	313
Allowance, Ending Balance	393	369
Recorded Investment in Finance Receivables, Ending Balance - Individually evaluated for impairment	632	575
Recorded Investment in Finance Receivables, Ending Balance - Collectively evaluated for impairment	26,084	24,550
Recorded Investment in Finance Receivables, Ending Balance	26,716	25,125
Customer
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	360	357
Receivables written off	(50)	(210)
Recoveries on receivables previously written off	23	52
Provision for credit losses	51	167
Adjustment due to sale of receivables	(1)	(3)
Foreign currency translation adjustment	(1)	(3)
Balance at end of period	382	360
Allowance, Ending Balance - Individually evaluated for impairment	61	56
Allowance, Ending Balance - Collectively evaluated for impairment	321	304
Allowance, Ending Balance	382	360
Recorded Investment in Finance Receivables, Ending Balance - Individually evaluated for impairment	632	575
Recorded Investment in Finance Receivables, Ending Balance - Collectively evaluated for impairment	18,239	17,423
Recorded Investment in Finance Receivables, Ending Balance	18,871	17,998
Dealer
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	6	5
Receivables written off	0	0
Recoveries on receivables previously written off	0	0
Provision for credit losses	2	1
Adjustment due to sale of receivables	0	0
Foreign currency translation adjustment	0	0
Balance at end of period	8	6
Allowance, Ending Balance - Individually evaluated for impairment	0	0
Allowance, Ending Balance - Collectively evaluated for impairment	8	6
Allowance, Ending Balance	8	6
Recorded Investment in Finance Receivables, Ending Balance - Individually evaluated for impairment	0	0
Recorded Investment in Finance Receivables, Ending Balance - Collectively evaluated for impairment	4,719	3,973
Recorded Investment in Finance Receivables, Ending Balance	4,719	3,973
Caterpillar Purchased Receivables
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	3	1
Receivables written off	0	0
Recoveries on receivables previously written off	0	0
Provision for credit losses	0	2
Adjustment due to sale of receivables	0	0
Foreign currency translation adjustment	0	0
Balance at end of period	3	3
Allowance, Ending Balance - Individually evaluated for impairment	0	0
Allowance, Ending Balance - Collectively evaluated for impairment	3	3
Allowance, Ending Balance	3	3
Recorded Investment in Finance Receivables, Ending Balance - Individually evaluated for impairment	0	0
Recorded Investment in Finance Receivables, Ending Balance - Collectively evaluated for impairment	3,126	3,154
Recorded Investment in Finance Receivables, Ending Balance	$ 3,126	$ 3,154