XML 77 R1.htm IDEA: XBRL DOCUMENT v3.3.0.814
Document And Entity Information - USD ($)
$ in Millions
 12 Months Ended
Aug. 31, 2015
Nov. 10, 2015
Feb. 27, 2015
Entity Registrant Name Northern Technologies International Corporation    
Entity Central Index Key 0000875582    
Trading Symbol ntic    
Current Fiscal Year End Date --08-31    
Entity Filer Category Accelerated Filer    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Well-known Seasoned Issuer No    
Entity Common Stock, Shares Outstanding (in shares)   4,538,317  
Entity Public Float     $ 77.1
Document Type 10-K    
Document Period End Date Aug. 31, 2015    
Document Fiscal Year Focus 2015    
Document Fiscal Period Focus FY    
Amendment Flag false