Summary of Company's Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Total debt	$ 139,890	$ 144,669
Current portion	(3,413)	(3,460)
Long-term debt, less current maturities	$ 136,477	$ 141,209
U.S. Revolving Note (U.S. Dollar Denominations)
Debt Instrument [Line Items]
Interest Rate	4.02%	3.07%
Total debt	$ 122,000	$ 129,000
U.S. Revolving Note (Euro Denominations)
Debt Instrument [Line Items]
Interest Rate	1.50%
Total debt	$ 5,727
DEG China Loan
Debt Instrument [Line Items]
Interest Rate	4.25%	4.25%
Total debt	$ 913	$ 1,919
DEG Vietnam Loan
Debt Instrument [Line Items]
Interest Rate	5.21%	5.21%
Total debt	$ 11,250	$ 13,750

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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