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Commitments and Contingencies (Details) $ in Millions, $ in Millions | 3 Months Ended | 6 Months Ended | 9 Months Ended
--- | --- | --- | ---
Dec. 31, 2019 USD ($) | Mar. 31, 2019 USD ($) | Mar. 31, 2018 USD ($) | Jun. 30, 2019 CAD ($)
Loss Contingency, Damages Sought, Value | $ 450.0 |  |  | $ 10.0
Income Tax Examination, Penalties Accrued | 22.2 |  |  |
IRS-Walter Energy Claim 1 [Member] |  |  |  |
Loss Contingency, Damages Sought, Value | 554.3 |  |  |
IRS-Walter Energy Claim 2 [Member] |  |  |  |
Loss Contingency, Damages Sought, Value | $ 860.4 |  |  |
Product Concentration Risk [Member] |  |  |  |
Operating Leases |  |  |  |
Product Warranty Expense |  | $ 14.1 | $ 9.8 |

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