v3.7.0.1
Document and Entity Information - shares
shares in Thousands
6 Months Ended
Jun. 30, 2017
Jul. 31, 2017
Entity Registrant Name GENERAL COMMUNICATION INC  
Entity Central Index Key 0000808461  
Current Fiscal Year End Date --12-31  
Entity Filer Category Accelerated Filer  
Document Type 10-Q  
Document Period End Date Jun. 30, 2017  
Document Fiscal Year Focus 2017  
Document Fiscal Period Focus Q2  
Amendment Flag false  
Common Stock - Class A [Member]    
Entity Common Stock Shares Outstanding   33,049
Common Stock - Class B [Member]    
Entity Common Stock Shares Outstanding   3,052