Goodwill and Other Intangible Assets - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
	Oct. 31, 2014	Oct. 31, 2013	Oct. 31, 2014	Oct. 31, 2013	Jan. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 5,661,000		$ 5,661,000		$ 4,320,000
Goodwill impairment			0
Aggregate amortization expense	$ 458,000	$ 164,000	$ 982,000	$ 493,000
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life of intangible assets			15 years
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life of intangible assets			8 years