Business Segment and Geographic Region Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012 item	Dec. 31, 2011	Dec. 31, 2010
Business Segment and Geographic Region Information
Number of business segments									1
Revenue by product lines
Revenue	$ 44,624	$ 44,640	$ 59,114	$ 55,007	$ 60,411	$ 72,455	$ 93,380	$ 93,170	$ 203,385	$ 319,416	$ 275,212
Ion implantation systems, services, and royalties
Revenue by product lines
Revenue									156,090	237,857	232,335
Other systems and services
Revenue by product lines
Revenue									$ 47,295	$ 81,559	$ 42,877