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Background and Basis of Presentation - Fair Value of Financial Instruments (Details) € in Millions, $ in Millions		3 Months Ended
	Apr. 06, 2021 USD ($)	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)	Apr. 06, 2021 EUR (€) $ / €
Fair Value of Financial Instruments
Unrealized loss on foreign currency forward contracts		$ 0.0	$ 6.2
Investments restricted to the payment of post-retirement employee benefits		10.8		$ 9.5
Itasa
Fair Value of Financial Instruments
Unrealized loss on foreign currency forward contracts			$ 6.2
Derivative, loss on derivative	$ 5.1
North America
Fair Value of Financial Instruments
Cost of marketable securities		0.6
North America \| Fair Value \| Level 1 \| Other Noncurrent Assets
Fair Value of Financial Instruments
Fair value of marketable securities		0.6
Germany \| Pension Benefits
Fair Value of Financial Instruments
Investments restricted to the payment of post-retirement employee benefits		2.4
Germany \| Other Noncurrent Assets \| Pension Benefits
Fair Value of Financial Instruments
Investments restricted to the payment of post-retirement employee benefits		1.7
Germany \| Prepaid Expenses and Other Current Assets \| Pension Benefits
Fair Value of Financial Instruments
Investments restricted to the payment of post-retirement employee benefits		$ 0.7
Foreign Exchange Forward \| Itasa
Fair Value of Financial Instruments
Derivative, notional amount \| €					€ 205.9
Derivative, forward exchange rate \| $ / €					1.203