Principal Maturities of Debt (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Debt maturing in 2015	$ 5,306
Debt maturing in 2016	5,138
Debt maturing in 2017	6,531
Debt maturing in 2018	6,996
Debt maturing in 2019	66,804
Total debt	90,775us-gaap_LongTermDebt	82,320us-gaap_LongTermDebt
US Term Note
Debt Instrument [Line Items]
Debt maturing in 2015	2,500
Debt maturing in 2016	2,812
Debt maturing in 2017	3,750
Debt maturing in 2018	4,063
Debt maturing in 2019	36,250
Total debt	49,375
Europe Term Loan
Debt Instrument [Line Items]
Debt maturing in 2015	1,213
Debt maturing in 2016	1,365
Debt maturing in 2017	1,820
Debt maturing in 2018	1,972
Debt maturing in 2019	17,593
Total debt	23,963
US Revolving Note
Debt Instrument [Line Items]
Debt maturing in 2019	12,000
Total debt	12,000
DEG Loan
Debt Instrument [Line Items]
Debt maturing in 2015	961
Debt maturing in 2016	961
Debt maturing in 2017	961
Debt maturing in 2018	961
Debt maturing in 2019	961
Total debt	4,805	5,561
Capital Lease
Debt Instrument [Line Items]
Debt maturing in 2015	632
Total debt	$ 632	$ 2,440

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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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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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