GOODWILL AND INTANGIBLE ASSETS (Details) (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Goodwill and intangible assets
Impairment charges on goodwill			$ 28,032,000
Balance of goodwill and intangible assets, net
Goodwill	1,616,154,000	1,358,524,000	989,493,000
Intangible assets with indefinite lives	378,964,000	351,488,000
Intangible assets with definite lives, net	103,940,000	26,619,000
Total goodwill and intangible assets, net	2,099,058,000	1,736,631,000
Minimum
Goodwill and intangible assets
Discount rates used for impairment assessment of goodwill (as a percent)	13.00%	13.00%
Discount rates used for impairment assessment of indefinite-lived intangible assets (as a percent)	10.00%	13.00%
Royalty rates used for impairment assessment of indefinite-lived intangible assets (as a percent)	1.00%	1.00%
Maximum
Goodwill and intangible assets
Discount rates used for impairment assessment of goodwill (as a percent)	25.00%	20.00%
Discount rates used for impairment assessment of indefinite-lived intangible assets (as a percent)	18.00%	20.00%
Royalty rates used for impairment assessment of indefinite-lived intangible assets (as a percent)	9.00%	9.00%
Search & Applications
Goodwill and intangible assets
Impairment charges on indefinite-lived intangible assets			11,000,000
Shoebuy
Goodwill and intangible assets
Impairment charges on goodwill			28,000,000
Impairment charges on indefinite-lived intangible assets			4,500,000
Balance of goodwill and intangible assets, net
Goodwill	21,719,000	21,719,000	21,712,000
Connected Ventures
Balance of goodwill and intangible assets, net
Goodwill	$ 8,267,000	$ 8,267,000	$ 8,436,000

The discount rate applied in annual goodwill impairment assessment.

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- Definition

The discount rate applied in annual indefinite-lived intangible assets impairment assessment.

+ References

No definition available.

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- Definition

The royalty rates used in annual indefinite-lived intangible assets impairment assessment.

+ References

No definition available.

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- Definition

Sum of the carrying amounts of all intangible assets, including goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

No definition available.

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- Definition

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

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Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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- Definition

Loss recognized during the period that results from the write-down of goodwill after comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill. Goodwill is assessed at least annually for impairment.

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Carrying amount of assets (excluding financial assets) that lack physical substance, excluding goodwill, having a projected indefinite period of benefit.

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Impairment recognized during the period and allocated to the reportable segment that results from the write-down of indefinite-lived intangible assets after comparing the implied fair value of reporting unit indefinite-lived intangible assets with the carrying amount of that indefinite-lived intangible assets, which are assessed at least annually for impairment.

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