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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 |

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