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Property, Plant and Equipment - Additional Information (Detail) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Property, Plant and Equipment [Line Items]      
Depreciation of property, plant and equipment $ 64,782 $ 68,181 $ 73,390
Machinery and equipment 601,835 595,445  
Accumulated depreciation 595,147 575,959  
Test Systems Leased By Customers      
Property, Plant and Equipment [Line Items]      
Machinery and equipment 19,400 20,400  
Accumulated depreciation $ 10,500 $ 8,500