Finance Receivables (Details 2) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Losses
Allowance for credit losses	$ 511	$ 365	$ 534	$ 511
Allowance for credit losses as a percent of our recorded investment in finance receivables			1.89%	1.80%
Financing Receivable, Allowance for Credit Losses
Balance at beginning of year	511	365
Receivables written off	(38)	(235)
Recoveries on receivables previously written off	8	46
Provision for credit losses	53	350
Adjustment due to sale of receivables	0	(7)
Foreign currency translation adjustment	0	(8)
Balance at end of period	534	511
Allowance for Credit Losses
Individually evaluated for impairment			$ 329	$ 302
Collectively evaluated for impairment			205	209
Allowance, Ending Balance	511	365	534	511
Recorded Investment in Finance Receivables
Individually evaluated for impairment			891	937
Collectively evaluated for impairment			27,428	27,497
Recorded Investment in Finance Receivables, Ending Balance			28,319	28,434
Customer
Financing Receivable, Allowance for Credit Losses
Allowance for credit losses	486	353	495	486
Financing Receivable, Allowance for Credit Losses
Balance at beginning of year	486	353
Receivables written off	(38)	(235)
Recoveries on receivables previously written off	8	46
Provision for credit losses	39	337
Adjustment due to sale of receivables	0	(7)
Foreign currency translation adjustment	0	(8)
Balance at end of period	495	486
Allowance for Credit Losses
Individually evaluated for impairment			302	288
Collectively evaluated for impairment			193	198
Allowance, Ending Balance	486	353	495	486
Recorded Investment in Finance Receivables
Individually evaluated for impairment			813	859
Collectively evaluated for impairment			18,443	18,724
Recorded Investment in Finance Receivables, Ending Balance			19,256	19,583
Dealer
Financing Receivable, Allowance for Credit Losses
Allowance for credit losses	21	9	34	21
Financing Receivable, Allowance for Credit Losses
Balance at beginning of year	21	9
Receivables written off	0	0
Recoveries on receivables previously written off	0	0
Provision for credit losses	13	12
Adjustment due to sale of receivables	0	0
Foreign currency translation adjustment	0	0
Balance at end of period	34	21
Allowance for Credit Losses
Individually evaluated for impairment			27	14
Collectively evaluated for impairment			7	7
Allowance, Ending Balance	21	9	34	21
Recorded Investment in Finance Receivables
Individually evaluated for impairment			78	78
Collectively evaluated for impairment			4,171	4,082
Recorded Investment in Finance Receivables, Ending Balance			4,249	4,160
Caterpillar Purchased Receivables
Financing Receivable, Allowance for Credit Losses
Allowance for credit losses	4	3	5	4
Financing Receivable, Allowance for Credit Losses
Balance at beginning of year	4	3
Receivables written off	0	0
Recoveries on receivables previously written off	0	0
Provision for credit losses	1	1
Adjustment due to sale of receivables	0	0
Foreign currency translation adjustment	0	0
Balance at end of period	5	4
Allowance for Credit Losses
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			5	4
Allowance, Ending Balance	$ 4	$ 3	5	4
Recorded Investment in Finance Receivables
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			4,814	4,691
Recorded Investment in Finance Receivables, Ending Balance			$ 4,814	$ 4,691

-- None. No documentation exists for this element. --

No definition available.

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- Definition

This element represents the allowance for credit losses expressed as a percent of finance receivables which is net of unearned income.

+ References

No definition available.

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- Definition

Amount of gain (loss) from converting allowance reserve for credit loss to currency of reporting entity from amount denominated or measured in a different currency, which decreases (increases) the allowance for loan and lease losses.

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- Definition

Amount of reduction of allowance reserve for credit loss arising from sale of loan and lease portfolios.

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- Definition

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

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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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

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

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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

Amount of expense related to estimated loss from loan and lease transactions.

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