Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2012	Jun. 30, 2012	Feb. 01, 2013 Common stock	Feb. 01, 2013 Class B convertible common stock
Entity Registrant Name	IAC/INTERACTIVECORP
Entity Central Index Key	0000891103
Document Type	10-K
Document Period End Date	Dec. 31, 2012
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float		$ 3,754,179,431
Entity Common Stock, Shares Outstanding			78,471,784	5,789,499
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	FY