Basis of Presentation (Details)
3 Months Ended 9 Months Ended
Aug. 02, 2015
USD ($)
Jan. 31, 2016
USD ($)
segment
Jan. 25, 2015
USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]      
Number of reportable segments | segment   1  
Impairment of long-lived assets $ 1,901,000 $ 1,901,000 $ 5,767,000
Income Approach Valuation Technique | Impaired Long-Lived Assets      
Property, Plant and Equipment      
Estimated fair value $ 0