Segment Reporting and Geographic Information - (Tables)

3 Months Ended

Mar. 31, 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
	March 31,
	2013				2012
Systems and Software:
Inspection	$	24,879	60	%	$	22,856	50	%
Metrology	288		1	%	10,237		22	%
Lithography	3,700		9	%	—		—	%
Data Analysis and Review	4,157		10	%	4,547		10	%
Parts	5,546		13	%	5,504		12	%
Services	3,080		7	%	2,565		6	%
Total revenue	$	41,650	100	%	$	45,709	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
	March 31,
	2013		2012
United States	$	9,402	$	9,355
Taiwan	13,131		8,665
Japan	2,388		1,393
China	2,748		1,913
South Korea	3,423		14,492
Other Asia	5,408		5,104
Austria	286		2,598
Germany	2,525		373
Other Europe	2,339		1,816
Total revenue	$	41,650	$	45,709

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

Customers comprising 10% or more of revenue:

	Three Months Ended
	March 31,
	2013		2012
Customer A	18.5	%	—	%
Customer B	6.5	%	10.4	%
Customer C	3.4	%	30.7	%