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Organization (Details) - USD ($) $ in Millions |  |  | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Oct. 03, 2019 | Jul. 31, 2014 | Dec. 31, 2020 | Dec. 31, 2019 | Jun. 30, 2015 | Sep. 30, 2020 | Sep. 30, 2019
Segment Reporting Information [Line Items] |  |  |  |  |  |  |
Restructuring |  |  | $ 1.9 | $ 1.6 |  | $ 2.8 | $ 1.7
Restructuring and other charges |  |  | 1.4 | 2.4 |  |  |
Payments |  |  | 1.1 | 0.5 |  |  |
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage | 51.00% | 49.00% |  |  |  |  |
Pension costs (benefits) other then service |  |  | $ (0.8) | $ (0.7) |  |  |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent |  |  | 21.00% | 21.00% |  |  |
Payments to acquire interest in joint venture |  |  |  |  | $ 1.7 |  |
Proceeds from Other Equity, Gross Amount |  |  | $ 4.8 |  |  |  |
Intercompany Loan related to NMTC |  |  | 12.2 |  |  |  |
Investment Fund Contribution for NMTC |  |  | 16.5 |  |  |  |
Sub-CDE loan from NMTC |  |  | 16.2 |  |  |  |
Restricted Cash |  |  | 2.2 |  |  | $ 0.0 |
Mueller Co. [Member] |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |
Restructuring and other charges |  |  | $ 0.1 | $ 0.0 |  |  |

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