Segment Information and Enterprise-Wide Disclosure - Schedule of Net Sales by Countries (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales	$ 268,430	$ 285,247	$ 264,224	$ 236,303	$ 232,085	$ 250,694	$ 236,645	$ 222,738	$ 1,054,204	$ 942,162	$ 848,904
Percentage of net sales									100.00%	100.00%	100.00%
China
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									$ 593,098	$ 548,015	$ 507,783
Percentage of net sales									56.00%	58.00%	60.00%
United States
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									$ 86,276	$ 79,869	$ 76,870
Percentage of net sales									8.00%	8.00%	9.00%
Korea
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									$ 65,849	$ 60,672	$ 66,605
Percentage of net sales									6.00%	6.00%	8.00%
Germany
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									$ 74,303	$ 61,415	$ 57,036
Percentage of net sales									7.00%	7.00%	7.00%
Singapore
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									$ 58,570	$ 48,464	$ 51,742
Percentage of net sales									6.00%	5.00%	6.00%
Taiwan
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									$ 67,399	$ 59,087	$ 30,127
Percentage of net sales									6.00%	6.00%	4.00%
All Others
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales									$ 108,709	$ 84,640	$ 58,741
Percentage of net sales									11.00%	10.00%	6.00%