Segment Information - Segment Financial Information (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Segment Reporting Information [Line Items]
Operating profit	$ 189.7	$ 175.6
Stock-based compensation expense	(5.5)	(5.9)
Amortization of acquisition-related intangible assets	(0.2)	(0.2)
Other expense, net	1.9	0.7
Income before income taxes	187.8	174.9
Operating Segments
Segment Reporting Information [Line Items]
Operating profit	212.5	199.0
Corporate and Unallocated
Segment Reporting Information [Line Items]
Operating profit	(22.8)	(23.4)
Stock-based compensation expense	(5.5)	(5.9)
Corporate general costs	(17.1)	(13.9)
Restructuring and related charges	0.0	(1.2)
Amortization of acquisition-related intangible assets	(0.2)	(0.2)
Cost investment activity	0.0	(2.2)
Proprietary Products \| Operating Segments
Segment Reporting Information [Line Items]
Operating profit	193.4	182.6
Contract-Manufactured Products \| Operating Segments
Segment Reporting Information [Line Items]
Operating profit	$ 19.1	$ 16.4

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