Segment Information - Segment Financial Information (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Segment Reporting Information [Line Items]
Operating profit	$ 155.3	$ 189.7
Stock-based compensation expense	(8.5)	(5.5)
Asset impairment for planned sale of plant	11.3	0.0
Interest (income) expense, net	(2.6)	1.9
Income before income taxes and equity in net income of affiliated companies	157.9	187.8
Asset impairments	11.3	0.0
Operating Segments
Segment Reporting Information [Line Items]
Operating profit	188.1	212.5
Corporate and Unallocated
Segment Reporting Information [Line Items]
Operating profit	(32.8)	(22.8)
Stock-based compensation expense	(8.5)	(5.5)
Corporate general costs	(14.7)	(17.1)
Asset impairment for planned sale of plant	(9.4)	0.0
Amortization of acquisition-related intangible assets	(0.2)	(0.2)
Proprietary Products
Segment Reporting Information [Line Items]
Asset impairments	9.4
Proprietary Products \| Operating Segments
Segment Reporting Information [Line Items]
Operating profit	170.7	193.4
Contract-Manufactured Products \| Operating Segments
Segment Reporting Information [Line Items]
Operating profit	$ 17.4	$ 19.1

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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