Borrowing Arrangements - Schedule of Outstanding Borrowings (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Capital leases	$ 2,021	$ 2,161
Long term debt	44,581	52,214
Long term debt	44,581	52,214
Current portion	(18,886)	(26,825)
Debt non current	25,695	25,389
Credit Facility [Member]
Debt Instrument [Line Items]
Long term debt	0	7,146
Industrial Revenue Bonds ("IRB") [Member]
Debt Instrument [Line Items]
Long term debt	13,311	13,311
Promissory Notes (and Interest) [Member]
Debt Instrument [Line Items]
Long term debt	24,221	23,844
Minority Shareholder Loan [Member]
Debt Instrument [Line Items]
Long term debt	5,028	4,990
Term Loan [Member]
Debt Instrument [Line Items]
Long term debt	$ 0	$ 762

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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