Goodwill and Other Identifiable Intangible Assets - Changes in Carrying Amount of Goodwill by Segment (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2025 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 3,286.6
Foreign currency translation/other	23.9
Ending Balance	3,310.5
Flow
Goodwill [Roll Forward]
Beginning Balance	730.4
Foreign currency translation/other	19.5
Ending Balance	749.9
Water Solutions
Goodwill [Roll Forward]
Beginning Balance	1,392.7
Foreign currency translation/other	4.4
Ending Balance	1,397.1
Pool
Goodwill [Roll Forward]
Beginning Balance	1,163.5
Foreign currency translation/other	0.0
Ending Balance	$ 1,163.5