Property Plant and Equipment - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended
	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2014	Jul. 31, 2013
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 141,000	$ 136,000	$ 283,000	$ 265,000
Costs of maintenance and repairs	70,000	55,000	119,000	121,000
Selling, General and Administrative Expenses [Member]
Property, Plant and Equipment [Line Items]
Rent expense related to operations and construction projects	49,000	34,000	97,000	69,000
Cost of Sales [Member]
Property, Plant and Equipment [Line Items]
Rent expense related to operations and construction projects	$ 2,965,000	$ 782,000	$ 4,561,000	$ 1,799,000