XML 22 R1.htm IDEA: XBRL DOCUMENT v2.4.0.6
Document and Entity Information (USD $)
 9 Months Ended
Oct. 31, 2011
Dec. 07, 2011
Jul. 31, 2010
Entity Information [Line Items]      
Entity Registrant Name MFRI INC.    
Entity Central Index Key 0000914122    
Current Fiscal Year End Date --01-31    
Entity Filer Category Smaller Reporting Company    
Document Type 10-Q    
Document Period End Date Oct. 31, 2011    
Document Fiscal Year Focus 2011    
Document Fiscal Period Focus Q3    
Amendment Flag false    
Entity Common Stock, Shares Outstanding   6,912,771  
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Public Float     $ 34,981,103