Other Income (Expense) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Other Income and Expenses [Abstract]
Investment and interest income	$ 138	$ 100	$ 395	$ 280
Foreign exchange gains (losses)	(51)	(18)	(1)	(161)
License fee income	38	33	104	105
Net periodic pension and OPEB income (cost), excluding service cost	29	13	89	37
Gains (losses) on securities	(5)	20	33	51
Miscellaneous income (loss)	(14)	60	173	87
Total	$ 135	$ 208	$ 793	$ 399

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

No definition available.

Name:	cat_MiscellaneousIncomeLossNonoperating
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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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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

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Period Type:	duration

- Definition

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

+ References

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- Definition

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

+ References

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- References

No definition available.

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- Definition

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

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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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