Cat Financial Financing Activities (Details 3) (USD $) In Millions, unless otherwise specified	6 Months Ended	12 Months Ended
	Jun. 30, 2012	Dec. 31, 2011
Allowance for Credit Loss Activity
Balance at beginning of year	$ 366	$ 362
Receivables written off	(50)	(210)
Recoveries on receivables previously written off	23	52
Provision for credit losses	53	168
Other	(2)	(6)
Balance at end of period	390	366
Allowance for Credit Losses
Individually evaluated for impairment	61	56
Collectively evaluated for impairment	329	310
Ending Balance	390	366
Recorded Investment in Finance Receivables
Individually evaluated for impairment	632	575
Collectively evaluated for impairment	21,094	19,405
Ending Balance - recorded investment in finance receivables	21,726	19,980
Customer
Allowance for Credit Loss Activity
Balance at beginning of year	360	357
Receivables written off	(50)	(210)
Recoveries on receivables previously written off	23	52
Provision for credit losses	51	167
Other	(2)	(6)
Balance at end of period	382	360
Allowance for Credit Losses
Individually evaluated for impairment	61	56
Collectively evaluated for impairment	321	304
Ending Balance	382	360
Recorded Investment in Finance Receivables
Individually evaluated for impairment	632	575
Collectively evaluated for impairment	17,816	17,018
Ending Balance - recorded investment in finance receivables	18,448	17,593
Dealer
Allowance for Credit Loss Activity
Balance at beginning of year	6	5
Receivables written off	0	0
Recoveries on receivables previously written off	0	0
Provision for credit losses	2	1
Other	0	0
Balance at end of period	8	6
Allowance for Credit Losses
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	8	6
Ending Balance	8	6
Recorded Investment in Finance Receivables
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	3,278	2,387
Ending Balance - recorded investment in finance receivables	$ 3,278	$ 2,387