Segment Information - Segment Financial Information (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Information [Line Items]
Operating profit	$ 122.8	$ 155.3
Stock-based compensation expense	(5.0)	(8.5)
Loss on disposal of plant	0.0	(9.4)
Interest (income) expense, net	(4.6)	(2.6)
Income before income taxes and equity in net income of affiliated companies	127.4	157.9
Operating Segments
Segment Reporting Information [Line Items]
Operating profit	143.4	188.1
Corporate and Unallocated
Segment Reporting Information [Line Items]
Operating profit	(20.6)	(32.8)
Stock-based compensation expense	(5.0)	(8.5)
Corporate general costs	(15.4)	(14.7)
Loss on disposal of plant	0.0	(9.4)
Amortization of acquisition-related intangible assets	(0.2)	(0.2)
Proprietary Products \| Operating Segments
Segment Reporting Information [Line Items]
Operating profit	126.3	170.7
Contract-Manufactured Products \| Operating Segments
Segment Reporting Information [Line Items]
Operating profit	$ 17.1	$ 17.4

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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