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Debt - Carrying Value of Debt Outstanding (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Nov. 29, 2017
Debt Instrument [Line Items]
Capital lease and other financing obligations	$ 38,475	$ 38,736
Total debt	664,083	626,746
Less: current portion of long-term debt	(1,884)	(1,881)
Total long-term debt	662,199	624,865
Senior Notes \| Senior secured notes
Debt Instrument [Line Items]
Debt	$ 291,067	290,687
Interest rate	7.875%		7.875%
Debt issuance costs	$ 8,900	9,300
Line of Credit \| US ABL Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt	334,541	297,323
Line of Credit \| Canadian ABL Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt	0	0
Outstanding borrowing	800
Debt issuance costs	1,600
Line of Credit \| Canadian ABL Facility \| Revolving Credit Facility \| Long-term Debt
Debt Instrument [Line Items]
Debt issuance costs	800
Line of Credit \| Canadian ABL Facility \| Revolving Credit Facility \| Other Non-current Assets
Debt Instrument [Line Items]
Debt issuance costs	$ 800	$ 1,800