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Employee Benefit Plan - Additional Information (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
United States [Member] |  |  |
Schedule Of Pension And Other Postretirement Benefits Expected Benefit Payments [Line Items] |  |  |
Contribution pension plan | $ 110 | $ 119 | $ 116
Belgium [Member] |  |  |
Schedule Of Pension And Other Postretirement Benefits Expected Benefit Payments [Line Items] |  |  |
Contribution pension plan | $ 572 | $ 697 | $ 655

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- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. + References No definition available. + Details
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- Definition Schedule Of Pension And Other Postretirement Benefits Expected Benefit Payments [Line Items] + References No definition available. + Details
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- Details
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- Details
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