Document and Entity Information
6 Months Ended
Nov. 30, 2012
Jan. 01, 2013
Document and Entity Information    
Entity Registrant Name Mistras Group, Inc.  
Entity Central Index Key 0001436126  
Document Type 10-Q  
Document Period End Date Nov. 30, 2012  
Amendment Flag false  
Current Fiscal Year End Date --05-31  
Entity Current Reporting Status Yes  
Entity Filer Category Accelerated Filer  
Entity Common Stock, Shares Outstanding   28,161,857
Document Fiscal Year Focus 2013  
Document Fiscal Period Focus Q2