Quarterly report pursuant to Section 13 or 15(d)

Document and Entity Information

v3.10.0.1
Document and Entity Information - shares
9 Months Ended
Sep. 30, 2018
Oct. 31, 2018
Document and Entity Information [Abstract]    
Entity Registrant Name Synalloy Corporation  
Entity Central Index Key 0000095953  
Current Fiscal Year End Date --12-31  
Entity Filer Category Accelerated Filer  
Entity Common Stock, Shares Outstanding   8,870,988
Document Fiscal Year Focus 2018  
Document Fiscal Period Focus Q3  
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Sep. 30, 2018  
Emerging Growth Company false  
Smaller Reporting Company false