Annual report pursuant to Section 13 and 15(d)

Income Taxes (Textual) (Detail)

v3.6.0.2
Income Taxes (Textual) (Detail) - USD ($)
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Schedule Of Income Taxes [Line Items]        
Change of valuation allowance on foreign tax credit $ 0 $ 0 $ (491,000)  
Effective tax rate 35.00% 35.00% 35.00%  
Valuation allowances $ 3,706,000 $ 3,972,000    
Increase in valuation allowance 300,000      
Tax benefit of options exercises 1,900,000      
Addition to paid-in capital related to the cancellation of stock windfall pool 300,000      
Undistributed earnings 147,000,000      
Cash and short term investments 248,000,000      
Decrease in unrecognized tax benefits 400,000      
Lapse of statutes of limitations 475,000 664,000 $ 558,000  
Increase in tax position related to prior year 174,000 281,000 493,000  
Increases for tax positions related to the current year 70,000 3,302,000 73,000  
Unrecognized Tax Benefits 5,898,000 6,314,000 3,395,000 $ 3,387,000
Unrecognized tax would impact effective tax rate 2,500,000 2,400,000 2,000,000  
Interest and penalties related to uncertain tax positions 600,000 400,000 300,000  
Total Interest and penalties related to uncertain tax positions 200,000 $ 100,000 $ 0  
Income Tax Provision [Member]        
Schedule Of Income Taxes [Line Items]        
Lapse of statutes of limitations 200,000      
Minimum [Member]        
Schedule Of Income Taxes [Line Items]        
Lapse of statutes of limitations 0      
Maximum [Member]        
Schedule Of Income Taxes [Line Items]        
Lapse of statutes of limitations 1,500,000      
Foreign Subsidiaries [Member]        
Schedule Of Income Taxes [Line Items]        
Cash and short term investments 155,800,000      
France [Member]        
Schedule Of Income Taxes [Line Items]        
Tax net operating loss carryforwards 1,900,000      
Canada [Member]        
Schedule Of Income Taxes [Line Items]        
Tax net operating loss carryforwards 700,000      
United Kingdom [Member]        
Schedule Of Income Taxes [Line Items]        
Tax net operating loss carryforwards 500,000      
United States [Member]        
Schedule Of Income Taxes [Line Items]        
Tax net operating loss carryforwards 7,700,000      
State and Local Jurisdiction [Member]        
Schedule Of Income Taxes [Line Items]        
Tax net operating loss carryforwards 7,900,000      
US Government Agencies Short-term Debt Securities [Member]        
Schedule Of Income Taxes [Line Items]        
Tax credits carryforwards 500,000      
Significant foreign jurisdictions [Member]        
Schedule Of Income Taxes [Line Items]        
Tax credits carryforwards 1,700,000      
Research Tax Credit Carryforward [Member]        
Schedule Of Income Taxes [Line Items]        
Tax credits carryforwards $ 200,000