v3.25.4

Income Taxes (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Valuation allowance reversed	$ 12.8
Tax benefit from income tax holiday	$ 3.1	$ 33.2	$ 18.6
Benefit from income tax holiday on diluted earnings per share (in dollars per share)	$ 0.01	$ 0.13	$ 0.08
Repatriation of earnings estimated tax impact	$ 156.0
Unrecognized tax benefits that would impact effective tax rate	34.9
Liability for uncertain tax positions	32.6
Unrecognized tax benefits, reduction of deferred tax assets	3.5
Accrued and unpaid interest and penalties	$ 4.4	$ 4.5

Income Tax Holiday, Tax Benefit, Diluted Earnings Per Share

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The estimated tax impact (foreign withholding and federal income tax) that would be generated if undistributed earnings as of the balance sheet date were to be repatriated to the domestic country.

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Unrecognized Tax Benefits, Reduction Of Deferred Tax Assets

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The amount of income taxes from which a reporting entity is exempt or for which it will receive a reduction in income taxes as a result of the income tax holiday granted by the taxing jurisdiction.

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Amount recognized for uncertainty in income taxes classified as noncurrent.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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AMKOR TECHNOLOGY, INC. 10-K