Business Combinations, Divestitures, Discontinued Operations and Assets and Liabilities Held for Sale - Summary of Discontinued Operations (Detail) - USD ($) $ in Millions		12 Months Ended
	Oct. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Discontinued Operations and Disposal Groups [Abstract]
Total revenues		$ 94.2	$ 308.6	$ 79.2
Pretax (loss) earnings from operations		(16.3)	16.2	6.6
Pretax loss on divestitures and sales of assets	$ (26.3)	(24.0)	(0.7)	(6.0)
Pretax (loss) earnings		(40.3)	15.5	0.6
Income tax (benefit) expense		(9.4)	5.0	0.1
(Loss) Earnings from discontinued operations, net of income tax (benefit) expense		(30.9)	10.5	0.5
Net cash provided by (used for) operating activities		0.6	(31.6)	(8.2)
Additions to property, plant and equipment		(3.0)	(15.5)	(3.7)
Proceeds from divestitures and sales of assets		372.0	249.9	0.0
Net cash provided by (used for) investing activities		$ 369.0	$ 234.4	$ (3.7)