v3.8.0.1
DOCUMENT AND ENTITY INFORMATION - shares
9 Months Ended
Sep. 30, 2017
Nov. 03, 2017
Entity Registrant Name IAC/INTERACTIVECORP  
Entity Central Index Key 0000891103  
Current Fiscal Year End Date --12-31  
Entity Filer Category Large Accelerated Filer  
Document Type 10-Q  
Document Period End Date Sep. 30, 2017  
Document Fiscal Year Focus 2017  
Document Fiscal Period Focus Q3  
Amendment Flag false  
Common Stock    
Entity Common Stock, Shares Outstanding   76,195,855
Class B Convertible Common Stock    
Entity Common Stock, Shares Outstanding   5,789,499