Goodwill and Other Identifiable Intangible Assets - Changes in Carrying Amount of Goodwill by Segment (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 3,274.6
Foreign currency translation/other	(18.8)
Ending Balance	3,255.8
Water Solutions
Goodwill [Roll Forward]
Beginning Balance	1,400.6
Foreign currency translation/other	(3.6)
Ending Balance	1,397.0
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	(15.2)
Ending Balance	$ 751.9