Summary of Property, Plant and Equipment Attributed to Significant Countries (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Property, plant and equipment	$ 359,523	$ 321,562	$ 321,301
UNITED STATES
Segment Reporting Information [Line Items]
Property, plant and equipment	257,584	226,394	229,558
KOREA, REPUBLIC OF
Segment Reporting Information [Line Items]
Property, plant and equipment	39,562	33,441	32,400
JAPAN
Segment Reporting Information [Line Items]
Property, plant and equipment	23,648	25,248	23,619
Malaysia
Segment Reporting Information [Line Items]
Property, plant and equipment	19,212	19,180	19,878
TAIWAN, PROVINCE OF CHINA
Segment Reporting Information [Line Items]
Property, plant and equipment	16,073	14,151	11,333
All Other Segments
Segment Reporting Information [Line Items]
Property, plant and equipment	$ 3,444	$ 3,148	$ 4,513