Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Apr. 30, 2017	Apr. 30, 2016	Jan. 31, 2017
Income Tax Disclosure [Abstract]
(Benefit) provision for income taxes	$ (133)	$ 120
Income tax examination, description	With limited exceptions, the Company is no longer subject to federal, state, local or foreign examinations for years ending prior to January 31, 2012. However, carryforward attributes that were generated in tax years ending prior to January 31, 2013 may still be adjusted upon examination by state or local tax authorities if they either have been or will be used in a future period.
Threshold percentage for change in ownership	50.00%
Period of change in ownership	3 years
Unrecognized excess tax benefits attributable to stock option exercises			$ 1,199