Segment Reporting and Geographic Information - (Tables)

6 Months Ended

Jun. 30, 2013

Segment Reporting and Geographic Information [Abstract]

Schedule of revenue from external customers by Products and Services [Table Text Block]

The following table lists the different sources of revenue:

	Three Months Ended								Six Months Ended
	June 30,								June 30,
	2013				2012				2013				2012
Systems and Software:
Inspection	$	26,829	58	%	$	33,949	60	%	$	51,708	59	%	$	56,805	56	%
Metrology	5,869		13	%	8,782		16	%	6,157		7	%	19,019		19	%
Lithography	—		—	%	—		—	%	3,700		4	%	—		—	%
Data Analysis and Review	4,856		11	%	5,584		10	%	9,013		10	%	10,131		10	%
Parts	5,255		11	%	5,146		9	%	10,801		13	%	10,650		10	%
Services	3,250		7	%	2,865		5	%	6,330		7	%	5,430		5	%
Total revenue	$	46,059	100	%	$	56,326	100	%	$	87,709	100	%	$	102,035	100	%

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

For geographical revenue reporting, revenues are attributed to the geographic location in which the product is shipped.  Revenue by geographic region is as follows:

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2013		2012		2013		2012
United States	$	10,077	$	8,783	$	19,478	$	18,137
Taiwan	19,490		15,269		32,621		23,934
Japan	1,319		4,007		3,707		5,401
China	4,520		4,076		7,269		5,989
South Korea	1,644		10,842		5,067		25,334
Other Asia	3,167		4,899		8,575		10,003
Austria	174		4,982		460		7,580
Germany	1,550		1,368		4,075		1,741
Other Europe	4,118		2,100		6,457		3,916
Total revenue	$	46,059	$	56,326	$	87,709	$	102,035

Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block]

Customers comprising 10% or more of revenue:

	Six Months Ended
	June 30,
	2013		2012
Customer A	11.0	%	1.7	%
Customer B	10.8	%	5.3	%
Customer C	10.0	%	7.1	%
Customer D	2.1	%	18.4	%
Customer E	1.1	%	12.5	%