SEGMENT INFORMATION - Schedule of Revenue Disaggregated by Service (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting Information [Line Items]
Revenue	$ 995,075	$ 760,833
Operating segments | Match Group
Segment Reporting Information [Line Items]
Revenue	407,367	298,764
Operating segments | ANGI Homeservices
Segment Reporting Information [Line Items]
Revenue	255,311	150,745
Operating segments | Video
Segment Reporting Information [Line Items]
Revenue	66,162	50,577
Operating segments | Applications
Segment Reporting Information [Line Items]
Revenue	131,987	158,897
Operating segments | Publishing
Segment Reporting Information [Line Items]
Revenue	134,322	78,080
North America | Operating segments | ANGI Homeservices
Segment Reporting Information [Line Items]
Revenue	236,026	138,072
International
Segment Reporting Information [Line Items]
Revenue	337,495	212,235
Europe | Operating segments | ANGI Homeservices
Segment Reporting Information [Line Items]
Revenue	19,285	12,673
Direct revenue | Operating segments | Match Group
Segment Reporting Information [Line Items]
Revenue	392,737	287,752
Direct revenue | North America | Operating segments | Match Group
Segment Reporting Information [Line Items]
Revenue	211,357	175,328
Direct revenue | International | Operating segments | Match Group
Segment Reporting Information [Line Items]
Revenue	181,380	112,424
Indirect revenue | Operating segments | Match Group
Segment Reporting Information [Line Items]
Revenue	14,630	11,012
Marketplace revenue | North America | Operating segments | ANGI Homeservices
Segment Reporting Information [Line Items]
Revenue	165,608	129,644
Consumer connection revenue | North America | Operating segments | ANGI Homeservices
Segment Reporting Information [Line Items]
Revenue	149,060	116,000
Membership subscription revenue | North America | Operating segments | ANGI Homeservices
Segment Reporting Information [Line Items]
Revenue	15,627	12,752
Other revenue | North America | Operating segments | ANGI Homeservices
Segment Reporting Information [Line Items]
Revenue	921	892
Advertising and other revenue | Operating segments | Video
Segment Reporting Information [Line Items]
Revenue	11,771	4,827
Advertising and other revenue | North America | Operating segments | ANGI Homeservices
Segment Reporting Information [Line Items]
Revenue	70,418	8,428
Advertising and other revenue | Europe | Operating segments | ANGI Homeservices
Segment Reporting Information [Line Items]
Revenue	247	202
Consumer connection revenue | Europe | Operating segments | ANGI Homeservices
Segment Reporting Information [Line Items]
Revenue	14,367	8,465
Membership subscription revenue | Europe | Operating segments | ANGI Homeservices
Segment Reporting Information [Line Items]
Revenue	4,671	4,006
Subscription revenue | Operating segments | Video
Segment Reporting Information [Line Items]
Revenue	34,343	24,817
Media production and distribution revenue | Operating segments | Video
Segment Reporting Information [Line Items]
Revenue	20,048	20,933
Consumer | Operating segments | Applications
Segment Reporting Information [Line Items]
Revenue	110,074	130,332
Advertising revenue | Operating segments | Applications
Segment Reporting Information [Line Items]
Revenue	93,785	111,411
Total ANGI Homeservices revenue | Operating segments | Applications
Segment Reporting Information [Line Items]
Revenue	87,431	105,098
Other | Operating segments | Applications
Segment Reporting Information [Line Items]
Revenue	6,354	6,313
Subscription and other revenue | Operating segments | Applications
Segment Reporting Information [Line Items]
Revenue	16,289	18,921
Partnerships | Operating segments | Applications
Segment Reporting Information [Line Items]
Revenue	21,913	28,565
Advertising revenue | Operating segments | Applications
Segment Reporting Information [Line Items]
Revenue	21,877	28,492
Google advertising revenue | Operating segments | Applications
Segment Reporting Information [Line Items]
Revenue	21,146	27,709
Other | Operating segments | Applications
Segment Reporting Information [Line Items]
Revenue	731	783
Other revenue | Operating segments | Applications
Segment Reporting Information [Line Items]
Revenue	36	73
Premium Brands | Operating segments | Publishing
Segment Reporting Information [Line Items]
Revenue	38,808	26,000
Advertising revenue | Operating segments | Publishing
Segment Reporting Information [Line Items]
Revenue	37,585	25,655
Google advertising revenue | Operating segments | Publishing
Segment Reporting Information [Line Items]
Revenue	13,638	9,789
Other | Operating segments | Publishing
Segment Reporting Information [Line Items]
Revenue	23,947	15,866
Other revenue | Operating segments | Publishing
Segment Reporting Information [Line Items]
Revenue	1,223	345
Ask & Other | Operating segments | Publishing
Segment Reporting Information [Line Items]
Revenue	95,514	52,080
Advertising revenue | Operating segments | Publishing
Segment Reporting Information [Line Items]
Revenue	95,305	51,892
Google advertising revenue | Operating segments | Publishing
Segment Reporting Information [Line Items]
Revenue	88,692	44,687
Other | Operating segments | Publishing
Segment Reporting Information [Line Items]
Revenue	6,613	7,205
Other revenue | Operating segments | Publishing
Segment Reporting Information [Line Items]
Revenue	$ 209	$ 188