TRANSACTION AND INTEGRATION RELATED COSTS IN CONNECTION WITH THE COMBINATION - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Business Acquisition
Stock-based compensation expense	$ 22,474	$ 103,980	$ 69,433	$ 120,280
Angie's List
Business Acquisition
Transaction and integration related costs	255	25,980	3,578	29,660
Write-off due to deferred revenue	700	100	5,300	100
Stock-based compensation expense	$ 16,039	$ 96,938	$ 51,868	$ 96,938

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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