Cat Financial Financing Activities Cat Financing Activities (Details 2 Credit quality- Customer Receivables Aging by origination year -Vintage disclosure) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Receivables [Abstract]
Period after which Unpaid Installments are Considered as Past Due	30 days
Dealer \| Latin America \| 91+ days past due
Financing Receivable, Credit Quality Indicator
2017	$ 78
Finance Receivables
Financing Receivable, Credit Quality Indicator
Total Finance Receivables	21,632	$ 22,397
Finance Receivables \| Customer
Financing Receivable, Credit Quality Indicator
2020	5,585
2019	6,049
2018	3,564
2017	1,717
2016	712
Prior	572
Revolving Finance Receivables	380
Total Finance Receivables	18,579	18,687
Finance Receivables \| Customer \| North America
Financing Receivable, Credit Quality Indicator
Total Finance Receivables		8,152
Finance Receivables \| Customer \| North America \| Current
Financing Receivable, Credit Quality Indicator
2020	2,697
2019	2,711
2018	1,588
2017	660
2016	288
Prior	59
Revolving Finance Receivables	89
Total Finance Receivables	8,092
Finance Receivables \| Customer \| North America \| 31-60 days past due
Financing Receivable, Credit Quality Indicator
2020	41
2019	57
2018	39
2017	21
2016	9
Prior	3
Revolving Finance Receivables	1
Total Finance Receivables	171
Finance Receivables \| Customer \| North America \| 61-90 days past due
Financing Receivable, Credit Quality Indicator
2020	12
2019	24
2018	21
2017	13
2016	4
Prior	1
Revolving Finance Receivables	0
Total Finance Receivables	75
Finance Receivables \| Customer \| North America \| 91+ days past due
Financing Receivable, Credit Quality Indicator
2020	6
2019	29
2018	30
2017	20
2016	8
Prior	5
Revolving Finance Receivables	0
Total Finance Receivables	98
Finance Receivables \| Customer \| EAME
Financing Receivable, Credit Quality Indicator
Total Finance Receivables		3,084
Finance Receivables \| Customer \| EAME \| Current
Financing Receivable, Credit Quality Indicator
2020	903
2019	1,049
2018	684
2017	313
2016	92
Prior	28
Revolving Finance Receivables	0
Total Finance Receivables	3,069
Finance Receivables \| Customer \| EAME \| 31-60 days past due
Financing Receivable, Credit Quality Indicator
2020	6
2019	9
2018	6
2017	3
2016	1
Prior	0
Revolving Finance Receivables	0
Total Finance Receivables	25
Finance Receivables \| Customer \| EAME \| 61-90 days past due
Financing Receivable, Credit Quality Indicator
2020	4
2019	4
2018	1
2017	0
2016	1
Prior	1
Revolving Finance Receivables	0
Total Finance Receivables	11
Finance Receivables \| Customer \| EAME \| 91+ days past due
Financing Receivable, Credit Quality Indicator
2020	6
2019	8
2018	13
2017	8
2016	40
Prior	43
Revolving Finance Receivables	0
Total Finance Receivables	118
Finance Receivables \| Customer \| Asia/Pacific
Financing Receivable, Credit Quality Indicator
Total Finance Receivables		2,264
Finance Receivables \| Customer \| Asia/Pacific \| Current
Financing Receivable, Credit Quality Indicator
2020	1,027
2019	835
2018	403
2017	86
2016	13
Prior	5
Revolving Finance Receivables	0
Total Finance Receivables	2,369
Finance Receivables \| Customer \| Asia/Pacific \| 31-60 days past due
Financing Receivable, Credit Quality Indicator
2020	9
2019	24
2018	23
2017	7
2016	1
Prior	0
Revolving Finance Receivables	0
Total Finance Receivables	64
Finance Receivables \| Customer \| Asia/Pacific \| 61-90 days past due
Financing Receivable, Credit Quality Indicator
2020	3
2019	9
2018	7
2017	4
2016	0
Prior	0
Revolving Finance Receivables	0
Total Finance Receivables	23
Finance Receivables \| Customer \| Asia/Pacific \| 91+ days past due
Financing Receivable, Credit Quality Indicator
2020	3
2019	21
2018	12
2017	2
2016	0
Prior	0
Revolving Finance Receivables	0
Total Finance Receivables	38
Finance Receivables \| Customer \| Mining
Financing Receivable, Credit Quality Indicator
Total Finance Receivables		2,290
Finance Receivables \| Customer \| Mining \| Current
Financing Receivable, Credit Quality Indicator
2020	315
2019	615
2018	334
2017	180
2016	104
Prior	159
Revolving Finance Receivables	160
Total Finance Receivables	1,867
Finance Receivables \| Customer \| Mining \| 31-60 days past due
Financing Receivable, Credit Quality Indicator
2020	0
2019	0
2018	1
2017	0
2016	0
Prior	0
Revolving Finance Receivables	0
Total Finance Receivables	1
Finance Receivables \| Customer \| Mining \| 61-90 days past due
Financing Receivable, Credit Quality Indicator
2020	0
2019	1
2018	4
2017	2
2016	0
Prior	0
Revolving Finance Receivables	0
Total Finance Receivables	7
Finance Receivables \| Customer \| Mining \| 91+ days past due
Financing Receivable, Credit Quality Indicator
2020	1
2019	11
2018	8
2017	24
2016	0
Prior	0
Revolving Finance Receivables	1
Total Finance Receivables	45
Finance Receivables \| Customer \| Latin America
Financing Receivable, Credit Quality Indicator
Total Finance Receivables		1,233
Finance Receivables \| Customer \| Latin America \| Current
Financing Receivable, Credit Quality Indicator
2020	402
2019	393
2018	182
2017	64
2016	18
Prior	38
Revolving Finance Receivables	0
Total Finance Receivables	1,097
Finance Receivables \| Customer \| Latin America \| 31-60 days past due
Financing Receivable, Credit Quality Indicator
2020	0
2019	3
2018	3
2017	2
2016	0
Prior	0
Revolving Finance Receivables	0
Total Finance Receivables	8
Finance Receivables \| Customer \| Latin America \| 61-90 days past due
Financing Receivable, Credit Quality Indicator
2020	1
2019	1
2018	1
2017	1
2016	0
Prior	0
Revolving Finance Receivables	0
Total Finance Receivables	4
Finance Receivables \| Customer \| Latin America \| 91+ days past due
Financing Receivable, Credit Quality Indicator
2020	0
2019	13
2018	45
2017	25
2016	7
Prior	5
Revolving Finance Receivables	0
Total Finance Receivables	95
Finance Receivables \| Customer \| Caterpillar Power Finance
Financing Receivable, Credit Quality Indicator
Total Finance Receivables		1,664
Finance Receivables \| Customer \| Caterpillar Power Finance \| Current
Financing Receivable, Credit Quality Indicator
2020	149
2019	232
2018	138
2017	274
2016	97
Prior	132
Revolving Finance Receivables	129
Total Finance Receivables	1,151
Finance Receivables \| Customer \| Caterpillar Power Finance \| 31-60 days past due
Financing Receivable, Credit Quality Indicator
2020	0
2019	0
2018	18
2017	0
2016	0
Prior	3
Revolving Finance Receivables	0
Total Finance Receivables	21
Finance Receivables \| Customer \| Caterpillar Power Finance \| 61-90 days past due
Financing Receivable, Credit Quality Indicator
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving Finance Receivables	0
Total Finance Receivables	0
Finance Receivables \| Customer \| Caterpillar Power Finance \| 91+ days past due
Financing Receivable, Credit Quality Indicator
2020	0
2019	0
2018	3
2017	8
2016	29
Prior	90
Revolving Finance Receivables	0
Total Finance Receivables	130
Finance Receivables \| Dealer
Financing Receivable, Credit Quality Indicator
Total Finance Receivables	$ 3,053	3,710
Finance Receivables \| Dealer \| North America
Financing Receivable, Credit Quality Indicator
Total Finance Receivables		2,136
Finance Receivables \| Dealer \| EAME
Financing Receivable, Credit Quality Indicator
Total Finance Receivables		342
Finance Receivables \| Dealer \| Asia/Pacific
Financing Receivable, Credit Quality Indicator
Total Finance Receivables		437
Finance Receivables \| Dealer \| Mining
Financing Receivable, Credit Quality Indicator
Total Finance Receivables		4
Finance Receivables \| Dealer \| Latin America
Financing Receivable, Credit Quality Indicator
Total Finance Receivables		790
Finance Receivables \| Dealer \| Caterpillar Power Finance
Financing Receivable, Credit Quality Indicator
Total Finance Receivables		$ 1

Amount of financing receivable originated more than five years prior to current fiscal year.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
-Paragraph 79
-URI http://asc.fasb.org/extlink&oid=121647567&loc=SL82922352-210448

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919232-210447

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of financing receivable originated four years prior to current fiscal year.

+ References

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of financing receivable originated in current fiscal year.

+ References

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- Definition

Amount of financing receivable originated in fiscal year prior to current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919232-210447

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 55
-Paragraph 79
-URI http://asc.fasb.org/extlink&oid=121647567&loc=SL82922352-210448

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of financing receivable originated three years prior to current fiscal year.

+ References

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of financing receivable originated two years prior to current fiscal year.

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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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Period Type:	duration

- Definition

Amount of financing receivable that can be withdrawn, repaid and redrawn.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Threshold period for when financing receivable is considered past due, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Excludes threshold period past due to write off as uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919253-210447

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
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- References

No definition available.

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