Finance Receivables (Details 2) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses
Allowance for credit losses	$ 365	$ 343	$ 403	$ 365
Allowance for credit losses as a percent of our recorded investment in finance receivables			1.45%	1.33%
Financing Receivable, Allowance for Credit Losses
Balance at beginning of year	365	343
Receivables written off	(40)	(157)
Recoveries on receivables previously written off	10	43
Provision for credit losses	67	129
Adjustment due to sale of receivables	(2)	(1)
Foreign currency translation adjustment	3	8
Balance at end of period	403	365
Allowance for Credit Losses
Individually evaluated for impairment			$ 194	$ 149
Collectively evaluated for impairment			209	216
Allowance, Ending Balance	365	343	403	365
Recorded Investment in Finance Receivables
Individually evaluated for impairment			973	942
Collectively evaluated for impairment			26,863	26,549
Recorded Investment in Finance Receivables, Ending Balance			27,836	27,491
Customer
Financing Receivable, Allowance for Credit Losses
Allowance for credit losses	353	331	390	353
Financing Receivable, Allowance for Credit Losses
Balance at beginning of year	353	331
Receivables written off	(40)	(157)
Recoveries on receivables previously written off	10	43
Provision for credit losses	66	129
Adjustment due to sale of receivables	(2)	(1)
Foreign currency translation adjustment	3	8
Balance at end of period	390	353
Allowance for Credit Losses
Individually evaluated for impairment			194	149
Collectively evaluated for impairment			196	204
Allowance, Ending Balance	353	331	390	353
Recorded Investment in Finance Receivables
Individually evaluated for impairment			973	942
Collectively evaluated for impairment			18,787	18,847
Recorded Investment in Finance Receivables, Ending Balance			19,760	19,789
Dealer
Financing Receivable, Allowance for Credit Losses
Allowance for credit losses	9	10	9	9
Financing Receivable, Allowance for Credit Losses
Balance at beginning of year	9	10
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	9	9
Allowance for Credit Losses
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			9	9
Allowance, Ending Balance	9	10	9	9
Recorded Investment in Finance Receivables
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			4,061	4,241
Recorded Investment in Finance Receivables, Ending Balance			4,061	4,241
Caterpillar Purchased Receivables
Financing Receivable, Allowance for Credit Losses
Allowance for credit losses	3	2	4	3
Financing Receivable, Allowance for Credit Losses
Balance at beginning of year	3	2
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	4	3
Allowance for Credit Losses
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			4	3
Allowance, Ending Balance	$ 3	$ 2	4	3
Recorded Investment in Finance Receivables
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			4,015	3,461
Recorded Investment in Finance Receivables, Ending Balance			$ 4,015	$ 3,461

-- 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
-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
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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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-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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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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-Publisher FASB
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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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-Name Accounting Standards Codification
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-SubTopic 225
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