XML 82 R57.htm IDEA: XBRL DOCUMENT v3.4.0.3
Commitments and Contingencies - Additional Information (Detail) - USD ($)
 1 Months Ended 3 Months Ended
Jan. 31, 2014
Apr. 30, 2016
May. 04, 2013
Commitments and Contingencies Disclosure [Abstract]      
Estimated replacement cost     $ 672,000
Replacement cost charged against reserve $ 406,000    
Other accrued expenses   $ 266,000  
Amount received from supplier for recovery $ 450,000    
Lower product prices period   Through fiscal 2017