Income Taxes - Income Tax Payments (Net of Refunds) by Jurisdiction (Details) $ in Thousands	12 Months Ended
Dec. 31, 2025 USD ($)
Income Tax Paid, by Individual Jurisdiction [Line Items]
Total	$ 26,018
U.S.
Income Tax Paid, by Individual Jurisdiction [Line Items]
State and local	548
Germany
Income Tax Paid, by Individual Jurisdiction [Line Items]
Federal	2,828
Thuringia
Income Tax Paid, by Individual Jurisdiction [Line Items]
State and local	6,610
Saalburg-Ebersdorf
Income Tax Paid, by Individual Jurisdiction [Line Items]
State and local	6,478
Arneburg
Income Tax Paid, by Individual Jurisdiction [Line Items]
State and local	3,753
Rosenthal
Income Tax Paid, by Individual Jurisdiction [Line Items]
State and local	3,576
Torgau
Income Tax Paid, by Individual Jurisdiction [Line Items]
State and local	1,482
Other
Income Tax Paid, by Individual Jurisdiction [Line Items]
Foreign	$ 743

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Amount, after income tax refund received, of cash paid to federal (national) tax jurisdiction for tax on income.

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Amount, after refund, of cash paid to foreign, federal, state, and local jurisdictions as income tax.

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