BASIS OF PRESENTATION Basis of Presentation (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Reclassification between Performance (formerly online) and Brand (formerly offline) Advertising	$ 12.1	$ 21.8

Reclassification between Performance (formerly online) and Brand (formerly offline) Advertising

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration