Goodwill and Other Identifiable Intangible Assets - Changes in Carrying Amount of Goodwill by Segment (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2024 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 3,274.6
Foreign currency translation/other	6.2
Ending Balance	3,280.8
Water Solutions
Goodwill [Roll Forward]
Beginning Balance	1,400.6
Foreign currency translation/other	1.1
Ending Balance	1,401.7
Pool
Goodwill [Roll Forward]
Beginning Balance	1,106.9
Foreign currency translation/other	0.0
Ending Balance	1,106.9
Flow
Goodwill [Roll Forward]
Beginning Balance	767.1
Foreign currency translation/other	5.1
Ending Balance	$ 772.2