Document And Entity Information - USD ($)
shares in Millions, $ in Millions
 12 Months Ended
Dec. 31, 2016
Mar. 30, 2017
Jun. 30, 2016
Document And Entity Information [Abstract]      
Entity Registrant Name NUMEREX CORP /PA/    
Entity Central Index Key 0000870753    
Trading Symbol nmrx    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Current Fiscal Year End Date --12-31    
Entity Filer Category Accelerated Filer    
Entity Well-known Seasoned Issuer No    
Entity Common Stock, Shares Outstanding   19.6  
Entity Public Float     $ 146.1
Document Type 10-K    
Document Period End Date Dec. 31, 2016    
Amendment Flag false    
Document Fiscal Year Focus 2016    
Document Fiscal Period Focus FY