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Employee Benefit Plan - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	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

X

- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

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X

- Definition

Schedule Of Pension And Other Postretirement Benefits Expected Benefit Payments [Line Items]

+ References

No definition available.

+ Details

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X

- Details

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Namespace Prefix:
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X

- Details

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Period Type: