Finance Receivables (Details 3) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Allowance for Credit Losses
Allowance for credit losses	$ 343	$ 338	$ 365	$ 343
Allowance for credit losses as a percent of our recorded investment in finance receivables			1.33%	1.29%
Financing Receivable, Allowance for Credit Losses
Balance at beginning of year	343	338
Receivables written off	(157)	(158)
Recoveries on receivables previously written off	43	35
Provision for credit losses	129	133
Adjustment due to sale of receivables	(1)	(8)
Foreign currency translation adjustment	8	3
Balance at end of year	365	343
Allowance for Credit Losses
Individually evaluated for impairment			$ 149	$ 85
Collectively evaluated for impairment			216	258
Allowance, Ending balance	343	338	365	343
Recorded Investment in Finance Receivables
Individually evaluated for impairment			942	786
Collectively evaluated for impairment			26,549	25,769
Recorded Investment in Finance Receivables, Ending Balance			27,491	26,555
Customer
Financing Receivable, Allowance for Credit Losses
Allowance for credit losses	331	327	353	331
Financing Receivable, Allowance for Credit Losses
Balance at beginning of year	331	327
Receivables written off	(157)	(158)
Recoveries on receivables previously written off	43	35
Provision for credit losses	129	132
Adjustment due to sale of receivables	(1)	(8)
Foreign currency translation adjustment	8	3
Balance at end of year	353	331
Allowance for Credit Losses
Individually evaluated for impairment			149	85
Collectively evaluated for impairment			204	246
Allowance, Ending balance	331	327	353	331
Recorded Investment in Finance Receivables
Individually evaluated for impairment			942	786
Collectively evaluated for impairment			18,847	18,859
Recorded Investment in Finance Receivables, Ending Balance			19,789	19,645
Dealer
Financing Receivable, Allowance for Credit Losses
Allowance for credit losses	10	9	9	10
Financing Receivable, Allowance for Credit Losses
Balance at beginning of year	10	9
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 year	9	10
Allowance for Credit Losses
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			9	10
Allowance, Ending balance	10	9	9	10
Recorded Investment in Finance Receivables
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			4,241	4,479
Recorded Investment in Finance Receivables, Ending Balance			4,241	4,479
Caterpillar Purchased Receivables
Financing Receivable, Allowance for Credit Losses
Allowance for credit losses	2	2	3	2
Financing Receivable, Allowance for Credit Losses
Balance at beginning of year	2	2
Receivables written off	0	0
Recoveries on receivables previously written off	0	0
Provision for credit losses	1	0
Adjustment due to sale of receivables	0	0
Foreign currency translation adjustment	0	0
Balance at end of year	3	2
Allowance for Credit Losses
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			3	2
Allowance, Ending balance	$ 2	$ 2	3	2
Recorded Investment in Finance Receivables
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			3,461	2,431
Recorded Investment in Finance Receivables, Ending Balance			$ 3,461	$ 2,431

-- 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.

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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-Publisher FASB
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- Definition

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

+ References

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- References

No definition available.

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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.

+ References

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.

+ References

No definition available.

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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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- Definition

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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