Annual report pursuant to Section 13 and 15(d)

Document and Entity Information

v3.19.1
Document and Entity Information - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2018
Mar. 11, 2019
Jun. 30, 2018
Document and Entity Information [Abstract]      
Entity Registrant Name Synalloy Corporation    
Entity Central Index Key 0000095953    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Filer Category Accelerated Filer    
Entity Public Float     $ 165.7
Entity Common Stock, Shares Outstanding   8,964,874  
Document Fiscal Year Focus 2018    
Document Fiscal Period Focus FY    
Document Type 10-K    
Amendment Flag false    
Document Period End Date Dec. 31, 2018    
Smaller Reporting Company true    
Emerging Growth Company false    
Shell Company false