Inventories, net (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Inventories, net
Raw materials	$ 57,809,000		$ 56,942,000
Work in process	29,064,000		27,462,000
Finished goods (completed systems)	8,660,000		11,385,000
Inventories, net	95,533,000		95,789,000
Inventories, net
Cost of sales due to below normal production capacity	0	500,000
Dry strip product line, intellectual property rights and certain assets
Inventories, net
Inventory reserves	$ 24,600,000	$ 2,100,000	$ 25,100,000
Size of dry strip wafer equipment and products, Company license to make and sell (in millimeters)		300