Segment Reporting and Geographic Information (Tables)

12 Months Ended

Dec. 31, 2016

Segment Reporting and Geographic Information [Abstract]

Revenue from External Customers by Products and Services [Table Text Block]

The following table lists the different sources of revenue:

	Year Ended December 31,
	2016				2015				2014
Systems and software:
Process Control	$	146,652	63	%	$	144,858	66	%	$	112,408	63	%
Lithography	18,949		8	%	14,519		6	%	11,163		6	%
Software	29,795		13	%	27,291		12	%	24,042		13	%
Parts	25,343		11	%	24,072		11	%	20,334		11	%
Services	12,041		5	%	10,950		5	%	13,271		7	%
Total revenue	$	232,780	100	%	$	221,690	100	%	$	181,218	100	%

Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area [Table Text Block]

The Company’s significant operations outside the United States include sales, service and application offices in Europe and Asia. For geographical reporting, revenues are attributed to the geographic location in which the product is shipped. Revenue by geographic region is as follows:

	Year Ended December 31,
	2016		2015		2014
Revenues from third parties:
United States	$	30,876	$	46,778	$	56,963
Taiwan	68,211		55,548		49,532
South Korea	15,556		14,221		16,690
Singapore	35,517		27,310		14,551
Austria	2,049		3,557		752
Japan	11,875		13,216		9,449
Germany	9,759		29,378		9,142
China	33,720		17,152		11,521
Other Europe	18,720		11,403		9,362
Other Asia	6,497		3,127		3,256
Total revenue	$	232,780	$	221,690	$	181,218