CONSOLIDATED STATEMENT OF OPERATIONS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenue	$ 1,104,592	$ 828,434	$ 3,158,789	$ 2,356,654
Operating costs and expenses:
Cost of revenue (exclusive of depreciation shown separately below)	237,238	166,290	657,424	451,281
Selling and marketing expense	386,802	352,879	1,159,294	1,023,394
General and administrative expense	190,903	235,580	563,450	529,397
Product development expense	77,740	70,645	230,122	180,835
Depreciation	18,925	17,263	56,987	55,490
Amortization of intangibles	20,152	4,366	60,293	22,151
Total operating costs and expenses	931,760	847,023	2,727,570	2,262,548
Operating income (loss)	172,832	(18,589)	431,219	94,106
Interest expense	(27,610)	(25,036)	(81,471)	(74,556)
Other income (expense), net	8,113	(10,216)	174,635	(7,700)
Earnings (loss) before income taxes	153,335	(53,841)	524,383	11,850
Income tax benefit	18,242	279,480	15,887	322,809
Net earnings	171,577	225,639	540,270	334,659
Net earnings attributable to noncontrolling interests	(25,803)	(45,996)	(105,061)	(62,539)
Net earnings attributable to IAC shareholders	$ 145,774	$ 179,643	$ 435,209	$ 272,120
Per share information attributable to IAC shareholders:
Basic earnings per share (USD per share)	$ 1.75	$ 2.22	$ 5.22	$ 3.43
Diluted earnings per share (USD per share)	$ 1.49	$ 1.79	$ 4.55	$ 2.82
Stock-based compensation expense by function:
Stock-based compensation expense	$ 55,363	$ 134,472	$ 172,006	$ 207,362
Cost of revenue
Stock-based compensation expense by function:
Stock-based compensation expense	512	414	1,937	1,389
Selling and marketing expense
Stock-based compensation expense by function:
Stock-based compensation expense	1,837	20,970	5,679	24,420
General and administrative expense
Stock-based compensation expense by function:
Stock-based compensation expense	44,242	94,432	134,743	153,123
Product development expense
Stock-based compensation expense by function:
Stock-based compensation expense	$ 8,772	$ 18,656	$ 29,647	$ 28,430