Canadian Customs Duty Examination - Textuals (Details) $ in Millions, $ in Millions	1 Months Ended		3 Months Ended		6 Months Ended
	Mar. 31, 2018 USD ($)	Mar. 31, 2018 CAD ($)	Jul. 31, 2019 USD ($)	Jul. 31, 2019 CAD ($)	Jul. 31, 2019 USD ($)	Jul. 31, 2019 CAD ($)
Canadian Customs Duty Examination [Line Items]
Deferred higher dutiable value					$ 1.7	$ 2.2
CBSA
Canadian Customs Duty Examination [Line Items]
Value of bond issued for prepayments of additional duties	$ 20.9	$ 26.9
Deferred higher dutiable value			$ 0.5	$ 0.6	$ 9.7	$ 12.7