Segment Information (Schedule Of Selected Supplemental Balance Sheet Information) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Segment Reporting Information [Line Items]
Depreciation and amortization	$ 46.9	$ 66.2	$ 62.5
Capital expenditures	47.3	47.4	47.6
Intangible assets, net and goodwill	396.5	390.4
Inventories, net	328.7	301.7
Corporate
Segment Reporting Information [Line Items]
Depreciation and amortization	0.1	0.2	0.2
Capital expenditures	0.0	0.0	0.0
Intangible assets, net and goodwill	0.0	0.0
Inventories, net	0.0	0.0
Water Flow Solutions | Operating Segments
Segment Reporting Information [Line Items]
Depreciation and amortization	26.6	38.3	32.8
Capital expenditures	24.1	31.1	33.4
Intangible assets, net and goodwill	264.5	264.9
Inventories, net	197.2	187.3
Water Management Solutions | Operating Segments
Segment Reporting Information [Line Items]
Depreciation and amortization	20.2	27.7	29.5
Capital expenditures	23.2	16.3	$ 14.2
Intangible assets, net and goodwill	132.0	125.5
Inventories, net	$ 131.5	$ 114.4