XML 13 R1.htm IDEA: XBRL DOCUMENT v3.19.1
Document and Entity Information Document - shares
 3 Months Ended
Mar. 31, 2019
Apr. 16, 2019
Entity Information    
Entity Registrant Name Tennant Company  
Entity Central Index Key 0000097134  
Document Type 10-Q  
Document Period End Date Mar. 31, 2019  
Current Fiscal Year End Date --12-31  
Entity Current Reporting Status Yes  
Entity Filer Category Large Accelerated Filer  
Entity Common Stock, Shares Outstanding   18,164,119
Document Fiscal Year Focus 2019  
Document Fiscal Period Focus Q1  
Amendment Flag false  
Entity Emerging Growth Company false  
Entity Small Business false