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Derivative Financial Instruments - Additional Information (Details) - CAD ($) $ in Millions | 12 Months Ended
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Sep. 30, 2019 | Sep. 30, 2018
Canadian Dollar Forward Contract |  |
Derivative [Line Items] |  |
Foreign currency forward contract to hedge | $ 7.0 | $ 30.0
Canadian Subsidiary |  |
Derivative [Line Items] |  |
Denominated intercompany accounts payable | $ 9.3 | $ 20.4

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- Definition The premium (cost) of a hedge, expensed during the period. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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