Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Property, plant and equipment, accumulated depreciation and amortization	$ 481.8	$ 487.1
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	62,740,154	62,599,331
Common stock, shares outstanding	47,547,622	47,913,821
Treasury stock, shares	15,192,532	14,685,510