Information on Business Segments - Net Sales and Operating Income by Segment (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net sales	$ 1,261.2	$ 1,195.5	$ 3,464.9	$ 3,591.1
Operating income	$ 196.5	192.7	$ 481.0	592.0
Operating Income, Percentage Change vs. Prior Year	(2.00%)		(18.80%)
Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net sales	$ 1,261.2	1,195.5	$ 3,464.9	3,591.1
Net Sales, Percentage Change vs. Prior Year	(5.50%)		(3.50%)
Corporate [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Operating income	$ (36.7)	(30.6)	$ (117.7)	(94.0)
Operating Income, Percentage Change vs. Prior Year	(19.90%)		(25.20%)
Water Innovations [Member] \| Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net sales	$ 688.0	635.1	$ 1,899.2	1,928.7
Operating income	$ 164.2	152.7	$ 434.7	462.7
Net Sales, Percentage Change vs. Prior Year	8.30%		(1.50%)
Operating Income, Percentage Change vs. Prior Year	7.50%		(6.10%)
Outdoors [Member] \| Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net sales	$ 366.4	403.6	$ 1,031.9	1,184.4
Operating income	$ 52.0	47.4	$ 126.2	154.6
Net Sales, Percentage Change vs. Prior Year	(9.20%)		(12.90%)
Operating Income, Percentage Change vs. Prior Year	9.70%		(18.40%)
Security [Member] \| Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net sales	$ 206.8	156.8	$ 533.8	478.0
Operating income	$ 17.0	$ 23.2	$ 37.8	$ 68.7
Net Sales, Percentage Change vs. Prior Year	31.90%		11.70%
Operating Income, Percentage Change vs. Prior Year	(26.70%)		(45.00%)