Income Taxes (Details 2) (USD $)	Jan. 31, 2013	Jan. 31, 2012
Current deferred tax assets:
Accounts receivable	$ 150,000	$ 133,000
Inventories	1,117,000	1,130,000
Compensation expense	169,000	187,000
Contract loss	(25,000)	15,000
Other	64,000	84,000
Total current deferred tax assets	1,475,000	1,549,000
Non-current deferred tax assets:
Property, plant and equipment, principally due to differences in depreciation and capitalized interest	(843,000)	(133,000)
Building held for sale	62,000	70,000
Research and experimentation and alternative minimum tax credits	888,000	325,000
Stock-based compensation	0	0
Net operating loss carryforward	185,000	508,000
Total non-current deferred tax assets	292,000	770,000
Total deferred tax asset	1,767,000	2,319,000
Non-current deferred tax liabilities:
Identifiable intangibles	224,000	35,000
Net deferred tax asset	$ 1,543,000	$ 2,284,000