Finance Receivables (Details 2) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Losses
Allowance for credit losses	$ 511	$ 365	$ 434	$ 511
Allowance for credit losses as a percent of our recorded investment in finance receivables			1.57%	1.80%
Financing Receivable, Allowance for Credit Losses
Balance at beginning of year	511	365
Receivables written off	(238)	(235)
Recoveries on receivables previously written off	31	46
Provision for credit losses	144	350
Adjustment due to sale of receivables	(11)	(7)
Foreign currency translation adjustment	(3)	(8)
Balance at end of period	434	511
Allowance for Credit Losses
Individually evaluated for impairment			$ 221	$ 302
Collectively evaluated for impairment			213	209
Allowance, Ending Balance	511	365	434	511
Recorded Investment in Finance Receivables
Individually evaluated for impairment			743	937
Collectively evaluated for impairment			26,877	27,497
Recorded Investment in Finance Receivables, Ending Balance			27,620	28,434
Customer
Financing Receivable, Allowance for Credit Losses
Allowance for credit losses	486	353	385	486
Financing Receivable, Allowance for Credit Losses
Balance at beginning of year	486	353
Receivables written off	(238)	(235)
Recoveries on receivables previously written off	31	46
Provision for credit losses	120	337
Adjustment due to sale of receivables	(11)	(7)
Foreign currency translation adjustment	(3)	(8)
Balance at end of period	385	486
Allowance for Credit Losses
Individually evaluated for impairment			182	288
Collectively evaluated for impairment			203	198
Allowance, Ending Balance	486	353	385	486
Recorded Investment in Finance Receivables
Individually evaluated for impairment			665	859
Collectively evaluated for impairment			18,301	18,724
Recorded Investment in Finance Receivables, Ending Balance			18,966	19,583
Dealer
Financing Receivable, Allowance for Credit Losses
Allowance for credit losses	21	9	45	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	24	12
Adjustment due to sale of receivables	0	0
Foreign currency translation adjustment	0	0
Balance at end of period	45	21
Allowance for Credit Losses
Individually evaluated for impairment			39	14
Collectively evaluated for impairment			6	7
Allowance, Ending Balance	21	9	45	21
Recorded Investment in Finance Receivables
Individually evaluated for impairment			78	78
Collectively evaluated for impairment			4,401	4,082
Recorded Investment in Finance Receivables, Ending Balance			4,479	4,160
Caterpillar Purchased Receivables
Financing Receivable, Allowance for Credit Losses
Allowance for credit losses	4	3	4	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	0	1
Adjustment due to sale of receivables	0	0
Foreign currency translation adjustment	0	0
Balance at end of period	4	4
Allowance for Credit Losses
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			4	4
Allowance, Ending Balance	$ 4	$ 3	4	4
Recorded Investment in Finance Receivables
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			4,175	4,691
Recorded Investment in Finance Receivables, Ending Balance			$ 4,175	$ 4,691

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

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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.

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

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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

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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 writeoff of financing receivable, charged against allowance for credit loss.

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

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