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Product Replacement Costs - Additional Information (Detail) - USD ($)
$ in Millions
 1 Months Ended 3 Months Ended 12 Months Ended
Jan. 31, 2014
May 04, 2013
Jan. 31, 2017
Other Income and Expenses [Abstract]      
Estimated replacement cost   $ 0.7  
Replacement cost charged against reserve     $ 0.4
Other accrued expenses     $ 0.2
Amount received from supplier for recovery $ 0.5    
Lower product prices period     Through the first quarter of fiscal 2017.