GOODWILL AND INTANGIBLE ASSETS (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Dec. 31, 2013
Goodwill [Roll Forward]
Balance at beginning of period	$ 388,922
Foreign currency translation adjustments	(87)
Acqcuisitions	13,419
Balance at end of period	402,254
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Goodwill	514,254	500,922
Accumulated impairment losses	(112,000)	(112,000)
Goodwill	402,254
Affiliate Marketing [Member]
Goodwill [Roll Forward]
Balance at beginning of period	30,657
Foreign currency translation adjustments	(60)
Acqcuisitions	0
Balance at end of period	30,597
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Goodwill	30,597	30,657
Accumulated impairment losses	0	0
Goodwill	30,597
Dotomi Inc [Member]
Goodwill [Roll Forward]
Balance at beginning of period	206,861
Foreign currency translation adjustments	0
Acqcuisitions	0
Balance at end of period	206,861
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Goodwill	206,861	206,861
Accumulated impairment losses	0	0
Goodwill	206,861
Media [Member]
Goodwill [Roll Forward]
Balance at beginning of period	151,404
Foreign currency translation adjustments	(27)
Acqcuisitions	13,419
Balance at end of period	164,796
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Goodwill	276,796	263,404
Accumulated impairment losses	(112,000)	(112,000)
Goodwill	$ 164,796