GOODWILL AND INTANGIBLE ASSETS (Details2) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Balance of goodwill by reporting unit, including the changes in the carrying value of goodwill
Balance at the beginning of the period	$ 1,616,154,000	$ 1,358,524,000
Additions	67,781,000	264,439,000
(Deductions)	(14,014,000)	(807,000)
Goodwill Transfers In Out During Period
Foreign Exchange Translation	5,402,000	(6,002,000)
Balance at the end of the period	1,675,323,000	1,616,154,000
Search & Applications
Balance of goodwill by reporting unit, including the changes in the carrying value of goodwill
Balance at the beginning of the period	723,650,000	526,444,000
Additions		197,458,000
(Deductions)	(160,000)	(252,000)
Goodwill Transfers In Out During Period	14,572,000
Foreign Exchange Translation
Balance at the end of the period	738,062,000	723,650,000
Goodwill accumulated impairment losses	916,900,000	916,900,000	916,900,000
Match
Balance of goodwill by reporting unit, including the changes in the carrying value of goodwill
Balance at the beginning of the period	683,935,000	667,073,000
Additions	62,419,000	23,250,000
(Deductions)		(555,000)
Goodwill Transfers In Out During Period
Foreign Exchange Translation	4,878,000	(5,833,000)
Balance at the end of the period	751,232,000	683,935,000
HomeAdvisor
Balance of goodwill by reporting unit, including the changes in the carrying value of goodwill
Balance at the beginning of the period	111,658,000	109,947,000
Additions	5,317,000	1,880,000
(Deductions)
Goodwill Transfers In Out During Period
Foreign Exchange Translation	524,000	(169,000)
Balance at the end of the period	117,499,000	111,658,000
Felix
Balance of goodwill by reporting unit, including the changes in the carrying value of goodwill
Balance at the beginning of the period
Additions
(Deductions)
Goodwill Transfers In Out During Period	14,373,000
Foreign Exchange Translation
Balance at the end of the period	14,373,000
CityGrid Media
Balance of goodwill by reporting unit, including the changes in the carrying value of goodwill
Balance at the beginning of the period	32,124,000	17,751,000
Additions		14,373,000
(Deductions)	(3,179,000)
Goodwill Transfers In Out During Period	(28,945,000)
Foreign Exchange Translation
Balance at the end of the period		32,124,000
Local
Balance of goodwill by reporting unit, including the changes in the carrying value of goodwill
Balance at the beginning of the period	143,782,000	127,698,000
Additions	5,317,000	16,253,000
(Deductions)	(3,179,000)
Goodwill Transfers In Out During Period	(14,572,000)
Foreign Exchange Translation	524,000	(169,000)
Balance at the end of the period	131,872,000	143,782,000
Connected Ventures
Balance of goodwill by reporting unit, including the changes in the carrying value of goodwill
Balance at the beginning of the period	8,267,000	8,267,000
Additions
(Deductions)
Goodwill Transfers In Out During Period
Foreign Exchange Translation
Balance at the end of the period	8,267,000	8,267,000
Goodwill accumulated impairment losses	11,600,000	11,600,000	11,600,000
DailyBurn
Balance of goodwill by reporting unit, including the changes in the carrying value of goodwill
Balance at the beginning of the period	7,323,000	7,323,000
Additions
(Deductions)
Goodwill Transfers In Out During Period
Foreign Exchange Translation
Balance at the end of the period	7,323,000	7,323,000
Media
Balance of goodwill by reporting unit, including the changes in the carrying value of goodwill
Balance at the beginning of the period	15,590,000	15,590,000
Additions
(Deductions)
Goodwill Transfers In Out During Period
Foreign Exchange Translation
Balance at the end of the period	15,590,000	15,590,000
Shoebuy
Balance of goodwill by reporting unit, including the changes in the carrying value of goodwill
Balance at the beginning of the period	21,719,000	21,719,000
Additions
(Deductions)
Goodwill Transfers In Out During Period
Foreign Exchange Translation
Balance at the end of the period	21,719,000	21,719,000
Goodwill accumulated impairment losses	28,000,000	28,000,000	28,000,000
Tutor
Balance of goodwill by reporting unit, including the changes in the carrying value of goodwill
Balance at the beginning of the period	27,478,000
Additions	45,000	27,478,000
(Deductions)	(10,675,000)
Goodwill Transfers In Out During Period
Foreign Exchange Translation
Balance at the end of the period	16,848,000	27,478,000
Other
Balance of goodwill by reporting unit, including the changes in the carrying value of goodwill
Balance at the beginning of the period	49,197,000	21,719,000
Additions	45,000	27,478,000
(Deductions)	(10,675,000)
Goodwill Transfers In Out During Period
Foreign Exchange Translation
Balance at the end of the period	$ 38,567,000	$ 49,197,000