Acquisition - Assets Acquired and Liabilities Assumed (Details) CAD in Millions, $ in Millions	Jun. 06, 2016 USD ($)	Feb. 23, 2015 CAD	Feb. 23, 2015 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Business Acquisition [Line Items]
Goodwill				$ 36.0	$ 22.9	$ 22.9
Pine State
Business Acquisition [Line Items]
Accounts receivable	$ 35.5
Inventories	21.2
Deposits and prepayments, and other	0.9
Property and equipment	10.3
Goodwill	13.1
Other intangible assets	10.2
Less: Accrued liabilities, and other	(2.8)
Total consideration	$ 88.4
Karrys Bros
Business Acquisition [Line Items]
Total consideration		CAD 10.0	$ 8.0