BUSINESS COMBINATION - Narrative (Details) - USD ($) $ in Millions		3 Months Ended	9 Months Ended
Sep. 29, 2017	Sep. 30, 2017	Sep. 30, 2017
Business Acquisition [Line Items]
Pro-forma adjustment to increase (decrease) share-based compensation		$ (85.1)	$ (52.8)
Pro-forma adjustment to increase (decrease) transaction related costs		(22.1)	(25.6)
Pro-forma adjustment to increase (decrease) amortization of intangibles		$ 11.4	34.4
Severance and retention costs			$ 12.0
Angie's List
Business Acquisition [Line Items]
Ownership interest acquired (as a percent)	100.00%
Purchase price	$ 781.4

Business Acquisition, Pro Forma Information, Adjustment To Increase (Decrease) Amortization Of Intangible Assets

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- Definition

Business Acquisition, Pro Forma Information, Adjustment To Increase (Decrease) Share-Based Compensation

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Business Acquisition, Pro Forma Information, Adjustment to Increase (Decrease) Transaction Related Costs

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Severance and Retention Costs

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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