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Basis of Presentation and Nature of Operations - Narrative (Details) $ / shares in Units, $ in Millions		3 Months Ended
	Dec. 20, 2020 $ / shares	Mar. 31, 2022 USD ($) segment $ / shares	Mar. 31, 2021 $ / shares	Jan. 01, 2022 USD ($)	Dec. 31, 2021 USD ($) $ / shares	Mar. 10, 2021 $ / shares	Jan. 01, 2021 USD ($)	Jan. 01, 2020 USD ($)	Jan. 01, 2019 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of operating segments \| segment		2
Cash dividends declared per share (in USD per share) \| $ / shares	$ 5.00	$ 0	$ 5.00
Conversion price (in USD per share) \| $ / shares	$ 56.00					$ 51.00
Other capital		$ (572.7)			$ (578.1)		$ (20.9)	$ (20.9)	$ (20.9)
Retained earnings		$ (129.4)			$ (102.6)		$ 7.8	$ (8.0)	$ (7.9)
Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred tax liabilities				$ 1.9
Other capital				5.6
Retained earnings				1.0
Long-term debt				$ 8.5
2 1/4% Notes
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Conversion price (in USD per share) \| $ / shares		$ 26.00			$ 26.00
2 1/4% Notes \| Convertible Debt
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Debt instrument interest rate stated percentage		2.25%
Long-term debt		$ 145.9			$ 145.9