Segment Information and Revenue - Schedule of Net Sales by Direct Sales or Distributor and Location (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended		12 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 304,085	$ 264,224	$ 578,597	$ 500,527	$ 1,100,000
Percentage of net sales		100.00%	100.00%	100.00%	100.00%
Direct Sales
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 84,022	$ 83,919	$ 160,679	$ 166,034
Percentage of net sales		100.00%	100.00%	100.00%	100.00%
Distributor
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 220,063	$ 180,305	$ 417,918	$ 334,493
Percentage of net sales		100.00%	100.00%	100.00%	100.00%
China
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 166,565	$ 146,386	$ 314,756	$ 275,911
Percentage of net sales		55.00%	55.00%	54.00%	55.00%
China | Direct Sales
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 54,747	$ 54,855	$ 104,072	$ 108,189
Percentage of net sales		65.00%	65.00%	65.00%	65.00%
China | Distributor
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 111,818	$ 91,529	$ 210,684	$ 167,721
Percentage of net sales		51.00%	51.00%	50.00%	50.00%
United States
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 31,203	$ 23,776	$ 55,988	$ 44,975
Percentage of net sales		10.00%	9.00%	10.00%	9.00%
United States | Direct Sales
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 4,772	$ 4,404	$ 8,457	$ 8,461
Percentage of net sales		6.00%	5.00%	5.00%	5.00%
United States | Distributor
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 26,431	$ 19,372	$ 47,531	$ 36,514
Percentage of net sales		12.00%	11.00%	11.00%	11.00%
Korea
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 13,502	$ 15,804	$ 26,464	$ 33,363
Percentage of net sales		4.00%	6.00%	5.00%	7.00%
Korea | Direct Sales
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 3,474	$ 4,626	$ 7,551	$ 8,958
Percentage of net sales		4.00%	6.00%	5.00%	5.00%
Korea | Distributor
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 10,028	$ 11,179	$ 18,913	$ 24,406
Percentage of net sales		5.00%	6.00%	5.00%	7.00%
Germany
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 23,646	$ 19,031	$ 48,356	$ 36,454
Percentage of net sales		8.00%	7.00%	8.00%	7.00%
Germany | Direct Sales
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 2,820	$ 2,434	$ 5,925	$ 5,170
Percentage of net sales		3.00%	3.00%	4.00%	3.00%
Germany | Distributor
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 20,826	$ 16,597	$ 42,431	$ 31,284
Percentage of net sales		9.00%	9.00%	10.00%	9.00%
Singapore
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 20,195	$ 15,097	$ 36,313	$ 25,939
Percentage of net sales		7.00%	6.00%	6.00%	5.00%
Singapore | Direct Sales
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 624	$ 60	$ 912	$ 174
Percentage of net sales		1.00%		1.00%
Singapore | Distributor
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 19,571	$ 15,037	$ 35,401	$ 25,765
Percentage of net sales		9.00%	8.00%	8.00%	8.00%
Taiwan
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 16,750	$ 18,110	$ 36,799	$ 34,258
Percentage of net sales		6.00%	7.00%	6.00%	7.00%
Taiwan | Direct Sales
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 922	$ 1,741	$ 1,778	$ 4,554
Percentage of net sales		1.00%	2.00%	1.00%	3.00%
Taiwan | Distributor
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales		$ 15,828	$ 16,370	$ 35,021	$ 29,704
Percentage of net sales		7.00%	9.00%	8.00%	9.00%
All Others
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales	[1]	$ 32,224	$ 26,020	$ 59,921	$ 49,627
Percentage of net sales	[1]	10.00%	10.00%	11.00%	10.00%
All Others | Direct Sales
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales	[1]	$ 16,663	$ 15,799	$ 31,984	$ 30,528
Percentage of net sales	[1]	20.00%	19.00%	19.00%	19.00%
All Others | Distributor
Segment Reporting Revenue Reconciling Item [Line Items]
Net sales	[1]	$ 15,561	$ 10,221	$ 27,937	$ 19,099
Percentage of net sales	[1]	7.00%	6.00%	8.00%	6.00%

[1] Represents countries with less than 3% of the total net sales each.