Geographic and Segment Information - Additional Information (Detail) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018 USD ($) Customer	Jun. 30, 2017 USD ($) Customer	Jun. 30, 2018 USD ($) Customer Segments	Jun. 30, 2017 USD ($) Customer
Revenues from External Customers and Long-Lived Assets [Line Items]
Number of operating segments \| Segments			2
Total net sales	$ 199,685	$ 166,685	$ 365,504	$ 328,395
Total gross profit	53,854	46,662	98,435	88,232
Korea [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total net sales	58,060	67,979	112,750	133,062
Operating Segments [Member] \| Standard Products Group [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total net sales	118,740	79,046	207,103	157,191
Total gross profit	$ 31,631	21,902	$ 55,670	40,137
Operating Segments [Member] \| Restatement Adjustment [Member] \| Standard Products Group [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total net sales		6,021		12,035
Total gross profit		$ 1,237		$ 2,462
Customer Concentration Risk [Member] \| Net Sales [Member] \| Top Ten Customers [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk, percentage	67.00%	59.00%	63.00%	60.00%
Number of customers \| Customer	10	10	10	10
Customer Concentration Risk [Member] \| Net Sales [Member] \| Top Customer One [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk, percentage	28.90%	15.10%	23.90%	14.90%
Number of customers greater than ten percent threshold \| Customer	1	1	1	1
Geographic Concentration Risk [Member] \| Net Sales [Member] \| China [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk, percentage	70.30%	51.40%	69.10%	50.30%
Geographic Concentration Risk [Member] \| Net Sales [Member] \| Taiwan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk, percentage	23.80%	34.80%	24.10%	32.20%
Geographic Concentration Risk [Member] \| Property, Plant and Equipment [Member] \| Korea [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk, percentage			97.00%

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