BUSINESS COMBINATIONS - Purchase Price (Details) - Angie's List $ / shares in Units, $ in Thousands	Sep. 29, 2017 USD ($) $ / shares
Business Acquisition
Cash consideration for holders who elected to receive $8.50 in cash per share of Angie's List common stock	$ 1,900
Total purchase price	$ 781,384
Cash paid to holders of acquiree common stock (USD per share) \| $ / shares	$ 8.50
Class A Common Stock
Business Acquisition
Cash consideration for holders who elected to receive $8.50 in cash per share of Angie's List common stock	$ 1,913
Consideration transferred, equity interests	$ 763,684
Cash paid to holders of acquiree common stock (USD per share) \| $ / shares	$ 8.50
Class A Common Stock \| Stock Options
Business Acquisition
Consideration transferred, equity interests	$ 11,749
Class A Common Stock \| RSUs
Business Acquisition
Consideration transferred, equity interests	$ 4,038

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