Summary of Company's Debt (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Total debt	$ 90,775us-gaap_LongTermDebt	$ 82,320us-gaap_LongTermDebt
Current portion	(5,306)	(21,439)
Long-term debt, less current maturities	85,469us-gaap_LongTermDebtNoncurrent	60,881us-gaap_LongTermDebtNoncurrent
US Term Note
Debt Instrument [Line Items]
Interest Rate	2.00%
Total debt	49,375
Europe Term Loan
Debt Instrument [Line Items]
Interest Rate	1.81%
Total debt	23,963
US Revolving Note
Debt Instrument [Line Items]
Interest Rate	1.92%
Total debt	12,000
DEG Loan
Debt Instrument [Line Items]
Interest Rate	4.25%	4.25%
Total debt	4,805	5,561
Capital Lease
Debt Instrument [Line Items]
Interest Rate	4.20%	4.20%
Total debt	632	2,440
US Term Note
Debt Instrument [Line Items]
Interest Rate		2.50%
Total debt		24,500
Europe Term Note
Debt Instrument [Line Items]
Interest Rate		2.49%
Total debt		38,899
W.E.T. Term Note
Debt Instrument [Line Items]
Interest Rate		2.01%
Total debt		$ 10,920

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

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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