Cat Financial Financing Activities (Details TDR) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($) Contracts	Sep. 30, 2020 USD ($) Contracts	Sep. 30, 2021 USD ($) Contracts	Sep. 30, 2020 USD ($) Contracts
Customer
Finance receivables modified as TDRs
Pre-TDR Amortized Cost	$ 17	$ 76	$ 54	$ 149
Post-TDR Amortized Cost	13	76	44	149
TDRs which had been modified within twelve months of the default date
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	0	25	27	36
Customer \| North America
Finance receivables modified as TDRs
Pre-TDR Amortized Cost	1	1	5	10
Post-TDR Amortized Cost	1	1	5	10
TDRs which had been modified within twelve months of the default date
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	0	6	1	6
Customer \| EMEA
Finance receivables modified as TDRs
Pre-TDR Amortized Cost	1	0	1	0
Post-TDR Amortized Cost	1	0	1	0
TDRs which had been modified within twelve months of the default date
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	0	0	0	10
Customer \| Asia/Pacific
Finance receivables modified as TDRs
Pre-TDR Amortized Cost	4	4	4	12
Post-TDR Amortized Cost	4	4	4	12
TDRs which had been modified within twelve months of the default date
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	0	0	6	0
Customer \| Mining
Finance receivables modified as TDRs
Pre-TDR Amortized Cost	0	5	11	22
Post-TDR Amortized Cost	0	5	5	22
TDRs which had been modified within twelve months of the default date
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	0	1	0	1
Customer \| Latin America
Finance receivables modified as TDRs
Pre-TDR Amortized Cost	4	16	10	18
Post-TDR Amortized Cost	4	16	10	18
TDRs which had been modified within twelve months of the default date
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	0	0	15	1
Customer \| Caterpillar Power Finance
Finance receivables modified as TDRs
Pre-TDR Amortized Cost	7	50	23	87
Post-TDR Amortized Cost	3	50	19	87
TDRs which had been modified within twelve months of the default date
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	$ 0	$ 18	$ 5	$ 18
Dealer
Finance receivables modified as TDRs
Number of Contracts (in contracts) \| Contracts	0	0	0	0

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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- Definition

Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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