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v3.20.1

Organization (Details) - USD ($) $ in Millions |  |  | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Oct. 03, 2019 | Jul. 31, 2014 | Mar. 31, 2020 | Mar. 31, 2019 | Mar. 31, 2020 | Mar. 31, 2019 | Sep. 30, 2014
Segment Reporting Information [Line Items] |  |  |  |  |  |  |
Beginning balance |  |  |  |  | $ 1.7 | $ 0.9 |
Restructuring |  |  | $ 0.9 | $ 6.9 | 3.3 | 10.1 |
Payments |  |  |  |  | 2.7 | 2.6 |
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage | 51.00% | 49.00% |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost other than Service Cost |  |  | $ (0.8) | $ 1.0 | $ (1.5) | $ 0.9 |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent |  |  | 21.00% | 21.00% | 21.00% | 21.00% |
Payments to Acquire Interest in Joint Venture |  |  |  |  |  |  | $ 1.7
Mueller Co. [Member] |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |
Restructuring |  |  | $ 0.4 | $ 1.1 | $ 0.4 | $ 1.1 |

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