XML 14 R1.htm IDEA: XBRL DOCUMENT v3.7.0.1
Document and Entity Information - shares
3 Months Ended
Jun. 24, 2017
Jul. 21, 2017
Document And Entity Information [Abstract]    
Entity Registrant Name MONRO MUFFLER BRAKE INC  
Entity Central Index Key 0000876427  
Document Type 10-Q  
Document Period End Date Jun. 24, 2017  
Amendment Flag false  
Document Fiscal Year Focus 2018  
Document Fiscal Period Focus Q1  
Current Fiscal Year End Date --03-31  
Entity Filer Category Large Accelerated Filer  
Entity Common Stock Shares Outstanding   32,724,124