v3.25.4

Other (Income) Expense, Net - Schedule of Other (Income) Expense, Net (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Other Income and Expenses [Abstract]
Interest income	$ (343)	$ (415)	$ (365)
Interest expense	1,357	1,271	1,146
Exchange losses	323	227	370
Income from investments in equity securities, net	(368)	(14)	(340)
Net periodic defined benefit plan (credit) cost other than service cost	(615)	(633)	(498)
Other, net	(203)	(460)	153
Other (income) expense, net	$ 151	$ (24)	$ 466

Other nonoperating income and expense items not separately disclosed.

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Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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

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Amount of interest expense classified as nonoperating.

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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Amount of expense (reversal of expense) for net periodic benefit cost components, excluding service cost component, of defined benefit plan. Amount includes, but is not limited to, interest cost, expected (return) loss on plan asset, amortization of prior service cost (credit), amortization of (gain) loss, amortization of transition (asset) obligation, settlement (gain) loss, curtailment (gain) loss and certain termination benefits.

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

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Merck & Co., Inc. 10-K