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Commitments and Contingencies (Details) $ in Millions, $ in Millions | 12 Months Ended
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Sep. 30, 2020 USD ($) | Sep. 30, 2019 USD ($) | Sep. 30, 2019 CAD ($) | Sep. 30, 2018 USD ($)
Loss Contingency, Damages Sought, Value |  |  | $ 10.0 |
Document Period End Date | Sep. 30, 2020 |  |  |
Product Warranty Expense | $ 2.6 | $ 3.9 |  | $ 18.7
Accrued settlements | 0.2 | 0.2 |  |
Estimated Insurance Recoveries | 5.0 |  |  |
Accrued settlements | 0.2 | $ 0.2 |  |
Siemens [Member] |  |  |  |
Accrued settlements | 10.0 |  |  |
Accrued settlements | $ 10.0 |  |  |
Product Concentration Risk [Member] |  |  |  |
Product Warranty Expense |  |  |  | $ 14.1

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