EARNINGS (LOSS) PER SHARE - Summary (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Net earnings (loss)	$ 26,786	$ (72,158)	$ 40,695	$ (46,296)
Net (earnings) loss attributable to noncontrolling interests	(169)	397	(64)	1,402
Net earnings (loss) attributable to ANGI Homeservices Inc. shareholders	$ 26,617	$ (71,761)	$ 40,631	$ (44,894)
Weighted average basic shares outstanding (shares)	481,570	415,420	480,178	414,978
Dilutive securities including stock appreciation rights, stock options, RSUs and subsidiary denominated equity awards (shares)	39,269	0	31,452	0
Weighted average diluted shares outstanding (shares)	520,839	415,420	511,630	414,978
Earnings (loss) per share attributable to ANGI Homeservices Inc. shareholders:
Basic earnings per share (USD per share)	$ 0.06	$ (0.17)	$ 0.08	$ (0.11)
Diluted earnings per share (USD per share)	$ 0.05	$ (0.17)	$ 0.08	$ (0.11)
Stock options, warrants, and subsidiary denominated equity exchange of Exchangeable Notes and vesting of RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted earnings per share (shares)	200		300
Market-based awards and PSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted earnings per share (shares)	1,200	58,300	1,200	58,300

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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