Segment Reporting and Geographic Information (Tables)

12 Months Ended

Dec. 31, 2012

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,
	2010				2011				2012
Systems:
Inspection	$	105,904	54	%	$	91,825	49	%	$	128,917	59	%
Metrology	39,428		20	%	38,616		21	%	38,001		17	%
Data Analysis and Review	19,417		10	%	23,356		13	%	19,840		9	%
Parts	19,266		10	%	21,719		11	%	20,802		10	%
Services	11,290		6	%	11,680		6	%	10,926		5	%
Total revenue	$	195,305	100	%	$	187,196	100	%	$	218,486	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,
	2010		2011		2012
Revenues from third parties:
United States	$	45,243	$	52,910	$	42,108
Taiwan	48,455		26,898		61,319
South Korea	17,612		26,725		31,959
Singapore	30,305		16,344		26,183
Austria	1,841		15,960		11,423
Japan	7,725		14,925		15,444
Germany	8,191		14,657		8,990
China	24,201		11,124		12,266
Other Europe	11,732		7,653		8,794
Total revenue	$	195,305	$	187,196	$	218,486