Borrowing Arrangements - Schedule of Outstanding Borrowings (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Capital leases	$ 1,398	$ 1,773
Outstanding borrowings	86,325	66,153
Debt - current portion	(45,080)	(19,335)
Long-term debt	41,245	46,818
Revolving Credit and Security Agreement [Member]
Debt Instrument [Line Items]
Long term debt	40,320	20,349
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	26,212	25,395
Minority Shareholder Loan [Member]
Debt Instrument [Line Items]
Long term debt	$ 5,084	$ 5,325

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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