Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Deferred Tax Assets, Gross [Abstract]
Environmental and restructuring	$ 0.4	$ 1.4
Net operating loss carry-forwards and credits	5.7	15.3
Other assets and reserves	7.9	5.1
Deferred tax assets	14.0	21.8
Valuation allowance, net	(6.4)	(3.6)
Deferred tax assets, net of valuation allowance	7.6	18.2
Property, plant and equipment, net	(19.0)	(10.2)
Other liabilities	(0.4)	(0.2)
Deferred tax liabilities	(19.4)	(10.4)
Net deferred tax (liabilities)/assets	$ (11.8)
Net deferred tax (liabilities)/assets		$ 7.8