Financing Arrangements - Additional Information (Detail) (USD $)	12 Months Ended
	Jan. 31, 2014	Jan. 31, 2013
Debt Disclosure [Abstract]
Maximum borrowing amount of revolving loan	$ 4,250,000
Interest rate on borrowings under the line of credit	LIBOR plus 2.25%
Interest rate	2.25%
Available funds designated to cover letters of credit issued by Bank in support of project development activities	1,350,000
Maximum amount of standby letters of credits that may be outstanding	10,000,000
Borrowings outstanding under bank financing arrangements	$ 0	$ 0
Expiration date of financing arrangements	May 31, 2015
Ratio of total funded debt to EBITDA	2	2
Fixed charge coverage ratio	1.25	1.25
Ratio of senior funded debt to EBITDA	1.50	1.50