Other income (expense) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Other Income and Expenses [Abstract]
Investment and interest income	$ 96	$ 25	$ 189	$ 46
Foreign exchange gains (losses)	40	224	(32)	271
License fee income	43	37	74	69
Net periodic pension and OPEB income (cost), excluding service cost	(12)	66	(25)	134
Gains (losses) on securities	(10)	(47)	(21)	(59)
Miscellaneous income (loss)	(30)	(45)	(26)	52
Total	$ 127	$ 260	$ 159	$ 513

This element represents the miscellaneous nonoperating income and loss incurred during the period.

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount of expense (reversal of expense) for net periodic pension and postretirement costs excluding the current service cost component. Includes, but is not limited to, interest cost, actual return on plan assets, amortization of loss (gain), amortization of prior service cost (credit), amortization of transition obligation (asset), loss (gain) from a settlement or curtailment, and certain termination benefits.

+ References

No definition available.

+ Details

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Namespace Prefix:	cat_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Section S99
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Balance Type:	credit
Period Type:	duration

- Definition

Amount, before tax, of realized and unrealized gain (loss) from foreign currency transaction.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(7))
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Balance Type:	credit
Period Type:	duration

- Definition

Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
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-Name Accounting Standards Codification
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- References

No definition available.

+ Details

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- Definition

Amount of income (expense) related to nonoperating activities, classified as other.

+ References

+ Details

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- Definition

Ancillary revenue earned during the period from the consideration paid to the entity for the use of its rights and property by another party. Examples include licensing the use of copyrighted materials and leasing the extraction of natural resources.

+ References

+ Details

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