Segment Reporting and Geographic Information Geographic Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Segment Reporting Information [Line Items]
Revenues	$ 58,597	$ 46,960	$ 170,633	$ 131,627
UNITED STATES
Segment Reporting Information [Line Items]
Revenues	9,455	19,683	38,876	39,320
TAIWAN, PROVINCE OF CHINA
Segment Reporting Information [Line Items]
Revenues	9,035	14,592	38,623	34,774
JAPAN
Segment Reporting Information [Line Items]
Revenues	2,881	1,236	8,113	7,589
CHINA
Segment Reporting Information [Line Items]
Revenues	6,529	1,807	13,474	8,932
South Korea [Domain]
Segment Reporting Information [Line Items]
Revenues	2,945	1,434	13,184	9,873
Asia [Member]
Segment Reporting Information [Line Items]
Revenues	1,571	52	2,428	1,821
GERMANY
Segment Reporting Information [Line Items]
Revenues	8,716	3,166	24,741	8,418
Other Europe [Domain]
Segment Reporting Information [Line Items]
Revenues	6,897	3,100	10,347	8,193
Sales [Member]
Segment Reporting Information [Line Items]
Revenues	$ 58,597	$ 46,960	$ 170,633	$ 131,627