Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Line Items]
Deferred tax asset	$ 38,400
Valuation allowance	(13,118)	$ (11,029)
Deferred tax liabilities	200
Valuation allowance	1,286	741
Net deferred tax asset	24,134	32,376
Deferred tax asset, increase in equity	2,100
Net deferred tax asset	25,253	33,290
Operating loss carryforwards that would expire the next 5 years	3,000
Alternative minimum tax credit carryforward	1,100
Undistributed earnings	33,800
Cash held by foreign subsidiaries	25,800
Unrecognized tax benefits liability	489	27	$ 189	$ 444
Accrued interest and penalties are included in the unrecognized tax benefits	$ 100	2
Minimum
Income Tax Disclosure [Line Items]
Federal research and development tax credit carryforward expiration year	2027
Maximum
Income Tax Disclosure [Line Items]
Federal research and development tax credit carryforward expiration year	2034
Research And Development
Income Tax Disclosure [Line Items]
Tax credits carried forward	$ 1,500
Belgium and Luxemburg
Income Tax Disclosure [Line Items]
Valuation allowance	(500)
Federal and state
Income Tax Disclosure [Line Items]
Release of valuation allowance	200
Foreign Tax Authority
Income Tax Disclosure [Line Items]
Valuation allowance	(1,900)
Net operating loss carryforwards	62,400
State and Local Jurisdiction
Income Tax Disclosure [Line Items]
Net operating loss carryforwards	$ 54,600
Adjustments for New Accounting Pronouncement
Income Tax Disclosure [Line Items]
Decrease in deferred tax liabilities		100
Adjustments for New Accounting Pronouncement | Current Assets
Income Tax Disclosure [Line Items]
Decrease in deferred tax assets		9,200
Adjustments for New Accounting Pronouncement | Assets
Income Tax Disclosure [Line Items]
Decrease in deferred tax assets		$ 100