Segment Reporting and Geographic Information - Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Segment Reporting Information [Line Items]
Revenues	$ 60,892	$ 73,096
United States [Member]
Segment Reporting Information [Line Items]
Revenues	9,131	9,068
Taiwan [Member]
Segment Reporting Information [Line Items]
Revenues	11,031	14,467
Japan [Member]
Segment Reporting Information [Line Items]
Revenues	3,940	4,130
China [Member]
Segment Reporting Information [Line Items]
Revenues	16,044	17,971
South Korea [Member]
Segment Reporting Information [Line Items]
Revenues	10,771	17,230
Singapore [Member]
Segment Reporting Information [Line Items]
Revenues	2,016	4,282
Other Asia [Member]
Segment Reporting Information [Line Items]
Revenues	993	1,917
Germany [Member]
Segment Reporting Information [Line Items]
Revenues	1,850	1,324
Other Europe [Member]
Segment Reporting Information [Line Items]
Revenues	$ 5,116	$ 2,707