Inventories (Details) (USD $)	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2011
Raw materials	$ 7,627,000	$ 6,626,000
Work in process	2,619,000	2,005,000
Finished goods	21,000	381,000
Reserve for obsolete and slow moving inventory	(2,072,000)	(2,219,000)	(2,424,000)
Inventories, net	$ 8,195,000	$ 6,793,000