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Severance and Retention Costs, Restructured European Operations (Details) - Restructured European Operations [Member] - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2021 | Dec. 31, 2020
Severance and Retention Costs [Abstract] |  |
Total estimated expenses | $ 13.6 |
Remaining estimated expenses to be recognized through October 2021 | 0.4 |
Beginning balance | 12.4 |
Amounts expensed during the period | 2.2 |
Reserve adjustments during the period | (1.5) |
Net amount expensed during the period | 0.7 | $ 12.5
Amounts paid during the period | (11.9) |
Ending balance | 1.2 | $ 12.4
R&D Expenses [Member] |  |
Severance and Retention Costs [Abstract] |  |
Net amount expensed during the period | 0.1 |
SG&A Expenses [Member] |  |
Severance and Retention Costs [Abstract] |  |
Net amount expensed during the period | $ 0.6 |

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