Cat Financial Financing Activities (Details 3) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2013	Dec. 31, 2012
Allowance for Credit Loss Activity
Balance at beginning of year	$ 423	$ 366
Receivables written off	(22)	(149)
Recoveries on receivables previously written off	12	47
Provision for credit losses	16	160
Other	(3)	(1)
Balance at end of period	426	423
Allowance for Credit Losses
Individually evaluated for impairment	101	73
Collectively evaluated for impairment	325	350
Ending Balance	426	423
Recorded Investment in Finance Receivables
Individually evaluated for impairment	736	682
Collectively evaluated for impairment	22,837	22,626
Ending balance-recorded investment in finance receivables	23,573	23,308
Customer
Allowance for Credit Loss Activity
Balance at beginning of year	414	360
Receivables written off	(22)	(149)
Recoveries on receivables previously written off	12	47
Provision for credit losses	15	157
Other	(3)	(1)
Balance at end of period	416	414
Allowance for Credit Losses
Individually evaluated for impairment	101	73
Collectively evaluated for impairment	315	341
Ending Balance	416	414
Recorded Investment in Finance Receivables
Individually evaluated for impairment	736	682
Collectively evaluated for impairment	18,958	18,742
Ending balance-recorded investment in finance receivables	19,694	19,424
Dealer
Allowance for Credit Loss Activity
Balance at beginning of year	9	6
Receivables written off	0	0
Recoveries on receivables previously written off	0	0
Provision for credit losses	1	3
Other	0	0
Balance at end of period	10	9
Allowance for Credit Losses
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	10	9
Ending Balance	10	9
Recorded Investment in Finance Receivables
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	3,879	3,884
Ending balance-recorded investment in finance receivables	$ 3,879	$ 3,884

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This element represents the other activity, net, in the allowance for credit loss during the period not otherwise defined in the taxonomy.

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

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-Publisher FASB

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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- Definition

Amount of direct write-downs of financing receivables charged against the allowance.

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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- Definition

The sum of the periodic provision charged to earnings, based on an assessment of uncollectibility from the counterparty on account of loan, lease or other credit losses, to reduce these accounts to the amount that approximates their net realizable value.

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-Publisher SEC

-Name Regulation S-X (SX)

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