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Derivative Financial Instruments - Additional Information (Details) - CAD ($) $ in Millions | 6 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 | Sep. 30, 2019
Canadian Dollar Forward Contract |  |
Derivative [Line Items] |  |
Foreign currency forward contract to hedge | $ 4.0 | $ 7.0
Canadian Subsidiary |  |
Derivative [Line Items] |  |
Denominated intercompany accounts payable | $ 7.5 | $ 9.3

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- Details
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