Canadian Customs Duty Examination - Textuals (Details) - CBSA $ in Millions, $ in Millions	1 Months Ended		3 Months Ended	6 Months Ended
	Mar. 31, 2018 CAD ($)	Mar. 31, 2018 USD ($)	Jul. 31, 2020 USD ($)	Jul. 31, 2020 CAD ($)	Jul. 31, 2020 USD ($)
Canadian Customs Duty Examination [Line Items]
Value of bond issued for prepayments of additional duties	$ 26.9	$ 20.9
Taxes paid and deferred for higher dutiable values			$ 0.0		$ 0.0
Deferred higher dutiable value				$ 13.0	$ 9.7