Other Income (Expense) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Other Income and Expenses [Abstract]
Investment and interest income	$ 153	$ 81	$ 257	$ 180
Foreign exchange gains (losses)	14	(125)	50	(143)
License fee income	34	37	66	72
Net periodic pension and OPEB income (cost), excluding service cost	30	13	60	24
Gains (losses) on securities	41	28	38	31
Miscellaneous income (loss)	126	50	187	27
Total	$ 398	$ 84	$ 658	$ 191

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

+ Details

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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
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+ Details

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Balance Type:	credit
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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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+ Details

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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

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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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