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v3.22.1

Organization (Details) $ in Millions | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 31, 2022 USD ($) business_segments | Mar. 31, 2021 USD ($) | Mar. 31, 2022 USD ($) | Mar. 31, 2021 USD ($) | Sep. 30, 2021 USD ($) | Sep. 30, 2020 USD ($)
Segment Reporting Information [Line Items] |  |  |  |  |  |
Restructuring | $ 2.1 | $ 2.2 | $ 2.1 | $ 2.2 | $ 3.1 | $ 2.8
Restructuring and other charges | 0.6 | 0.8 | 3.0 | 2.2 |  |
Payments |  |  | 2.6 | 1.6 |  |
Pension costs (benefits) other then service | $ (1.0) | $ (0.8) | $ (2.0) | $ (1.6) |  |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent | 21.00% | 21.00% | 21.00% | 21.00% |  |
Number of Reportable Segments | business_segments | 2 |  |  |  |  |
Proceeds from Other Equity, Gross Amount | $ 4.8 |  | $ 4.8 |  |  |
Intercompany Loan related to NMTC | 12.2 |  | 12.2 |  |  |
Investment Fund Contribution for NMTC | 16.5 |  | 16.5 |  |  |
Sub-CDE loan from NMTC | 16.2 |  | 16.2 |  |  |
Mueller Co. [Member] |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Restructuring and other charges | $ 0.0 | $ 0.0 | $ 0.0 | $ 0.1 |  |

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