Annual report pursuant to Section 13 and 15(d)

Document And Entity Information

v3.3.1.900
Document And Entity Information - USD ($)
12 Months Ended
Dec. 31, 2015
Mar. 01, 2016
Jun. 30, 2015
Document And Entity Information [Abstract]      
Document Type 10-K    
Amendment Flag false    
Document Period End Date Dec. 31, 2015    
Document Fiscal Period Focus FY    
Document Fiscal Year Focus 2015    
Entity Registrant Name COMMUNICATIONS SYSTEMS INC    
Entity Central Index Key 0000022701    
Current Fiscal Year End Date --12-31    
Entity Filer Category Accelerated Filer    
Entity Common Stock, Shares Outstanding   8,761,000  
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Well-known Seasoned Issuer No    
Entity Public Float     $ 72,920,000