GOODWILL AND INTANGIBLE ASSETS (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Balance of goodwill and intangible assets, net
Goodwill	$ 1,754,926,000us-gaap_Goodwill	$ 1,675,323,000us-gaap_Goodwill	$ 1,616,154,000us-gaap_Goodwill
Intangible assets with indefinite lives	405,234,000	376,329,000
Intangible assets with definite lives, net	86,702,000us-gaap_FiniteLivedIntangibleAssetsNet	69,007,000us-gaap_FiniteLivedIntangibleAssetsNet
Total goodwill and intangible assets, net	2,246,862,000	2,120,659,000
Search & Applications
Goodwill and intangible assets
Goodwill, Impaired, Accumulated Impairment Loss	916,900,000	916,900,000	916,900,000
Balance of goodwill and intangible assets, net
Goodwill	774,822,000	738,062,000	723,650,000
Intangible assets with indefinite lives	211,095,000	195,805,000
Intangible assets with definite lives, net	44,355,000	40,550,000
ShoeBuy
Goodwill and intangible assets
Goodwill, Impaired, Accumulated Impairment Loss	28,000,000	28,000,000	28,000,000
Balance of goodwill and intangible assets, net
Goodwill	21,719,000	21,719,000	21,719,000
Media - Connected Ventures
Goodwill and intangible assets
Goodwill, Impaired, Accumulated Impairment Loss	11,600,000	11,600,000	11,600,000
Balance of goodwill and intangible assets, net
Goodwill	$ 8,267,000	$ 8,267,000	$ 8,267,000

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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Carrying amount of finite-lived intangible assets, indefinite-lived intangible assets and goodwill. Goodwill is an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Intangible assets are assets, not including financial assets, lacking physical substance.

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