Amount for accounts payable to related parties.

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Name:	us-gaap_AccountsPayableRelatedPartiesCurrentAndNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Derivative Financial Instruments - Additional Information (Details) - CAD ($) $ in Millions	Mar. 28, 2018	Jun. 30, 2018	Sep. 30, 2017
Canadian Dollar Forward Contract
Derivative [Line Items]
Foreign currency forward contract to hedge	$ 30.0
Canadian Subsidiary
Derivative [Line Items]
Denominated intercompany accounts payable		$ 38.9	$ 26.1