CONSOLIDATED STATEMENT OF COMPREHENSIVE OPERATIONS (Unaudited) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Net earnings (loss)		$ 80,557	$ (190,542)	$ 109,020	$ (182,608)
Other comprehensive income (loss), net of tax:
Change in foreign currency translation adjustment	[1]	18,788	(3,341)	40,698	12,404
Change in unrealized gains and losses of available-for-sale securities (net of tax benefits)	[2]	(4,028)	(3,782)	(4,026)	1,655
Total other comprehensive income (loss), net of tax		14,760	(7,123)	36,672	14,059
Comprehensive income (loss)		95,317	(197,665)	145,692	(168,549)
Comprehensive income attributable to noncontrolling interests		(18,442)	(3,553)	(23,830)	(4,379)
Comprehensive income (loss) attributable to IAC shareholders		$ 76,875	$ (201,218)	$ 121,862	$ (172,928)

[1] The three and six months ended June 30, 2017 and 2016 include amounts reclassified out of other comprehensive income into earnings. See Note 6—Accumulated Other Comprehensive Loss for additional information.

[2] The three and six months ended June 30, 2017 and 2016 include unrealized gains reclassified out of other comprehensive income into earnings. See Note 3—Marketable Securities and Note 6—Accumulated Other Comprehensive Loss for additional information.