XML 13 R1.htm IDEA: XBRL DOCUMENT v3.25.3
Cover Page - shares
 9 Months Ended
Sep. 30, 2025
Oct. 31, 2025
Document Information [Line Items]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Sep. 30, 2025  
Document Transition Report false  
Entity File Number 001-39356  
Entity Registrant Name IAC Inc.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 84-3727412  
Entity Address, Address Line One 555 West 18th Street  
Entity Address, City or Town New York  
Entity Address, State or Province NY  
Entity Address, Postal Zip Code 10011  
City Area Code 212  
Local Phone Number 314-7300  
Title of 12(b) Security Common stock, par value $0.0001  
Trading Symbol IAC  
Security Exchange Name NASDAQ  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Central Index Key 0001800227  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q3  
Amendment Flag false  
Common Stock    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   71,643,545
Class B common stock    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   5,789,499