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Income Taxes - Cash Payments for Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Effective Income Tax Rate Reconciliation [Line Items]
Total	$ 125.2	$ 71.4	$ 90.8
United States
Effective Income Tax Rate Reconciliation [Line Items]
Federal	22.3
State	(1.0)
France
Effective Income Tax Rate Reconciliation [Line Items]
Income tax paid, foreign, after refund received	8.6
Germany - Federal
Effective Income Tax Rate Reconciliation [Line Items]
Income tax paid, foreign, after refund received	24.5
Germany - Eschweiler
Effective Income Tax Rate Reconciliation [Line Items]
Income tax paid, foreign, after refund received	21.8
Ireland
Effective Income Tax Rate Reconciliation [Line Items]
Income tax paid, foreign, after refund received	15.8
Other foreign
Effective Income Tax Rate Reconciliation [Line Items]
Income tax paid, foreign, after refund received	$ 33.2