Document and Entity Information - shares
 9 Months Ended
May 31, 2020
Jun. 30, 2020
Document and Entity Information    
Document Type 10-Q  
Document Period End Date May 31, 2020  
Entity Registrant Name CHASE CORP  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   9,442,659
Entity Central Index Key 0000830524  
Current Fiscal Year End Date --08-31  
Document Fiscal Year Focus 2020  
Document Fiscal Period Focus Q3  
Amendment Flag false