SEGMENT INFORMATION - Reconciliation of Adjusted EBITDA to Operating Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Segment Reporting, Other Significant Reconciling Item
Operating income (loss)	$ 23,262	$ (2,836)	$ 12,506	$ (1,448)
Stock-based compensation expense	22,053	11,839	46,959	16,300
Depreciation			12,070	6,214
Amortization of intangibles	15,778	2,750	32,084	4,117
Interest expense—third party	(3,011)	0	(5,665)	0
Interest expense—related party	(34)	(2,082)	(79)	(3,674)
Other income, net	1,053	505	1,409	736
Earnings (loss) before income taxes	21,270	(4,413)	8,171	(4,386)
Income tax benefit	1,753	4,388	5,738	30,248
Net earnings (loss)	23,023	(25)	13,909	25,862
Net (earnings) loss attributable to noncontrolling interests	(124)	279	105	1,005
Net earnings attributable to ANGI Homeservices Inc. shareholders	22,899	254	14,014	26,867
North America
Segment Reporting, Other Significant Reconciling Item
Operating income (loss)	26,110	1,784	20,745	8,208
Stock-based compensation expense	21,821	11,395	46,396	15,396
Depreciation	5,354	2,892	10,928	5,777
Amortization of intangibles	14,803	1,041	29,624	1,915
Adjusted EBITDA	68,088	17,112	107,693	31,296
Europe
Segment Reporting, Other Significant Reconciling Item
Operating income (loss)	(2,848)	(4,620)	(8,239)	(9,656)
Stock-based compensation expense	232	444	563	904
Depreciation	532	326	1,142	437
Amortization of intangibles	975	1,709	2,460	2,202
Adjusted EBITDA	$ (1,109)	$ (2,141)	$ (4,074)	$ (6,113)