Acquired Intangible Assets, Net (Definite-lived intangible assets) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Acquired Definite-Lived Intangible Assets [Line Items]
Acquired definite-lived intangible assets, gross	$ 67,175	$ 25,119
Acquired definite-lived intangible assets, net	47,404us-gaap_FiniteLivedIntangibleAssetsNet	16,014us-gaap_FiniteLivedIntangibleAssetsNet
Domain names [Member]
Acquired Definite-Lived Intangible Assets [Line Items]
Acquired definite-lived intangible assets, gross	5,140	2,482
Less: Accumulated amortization	(1,252)	(859)
Less: Impairment loss	(413)	(424)
Technology [Member]
Acquired Definite-Lived Intangible Assets [Line Items]
Acquired definite-lived intangible assets, gross	28,043	12,013
Less: Accumulated amortization	(7,627)	(3,450)
Less: Impairment loss	(859)	(887)
Non-compete agreement [Member]
Acquired Definite-Lived Intangible Assets [Line Items]
Acquired definite-lived intangible assets, gross	13,026	3,985
Less: Accumulated amortization	(4,426)	(1,584)
Customer relationship [Member]
Acquired Definite-Lived Intangible Assets [Line Items]
Acquired definite-lived intangible assets, gross	5,110	2,973
Less: Accumulated amortization	(1,552)	(507)
Distributor relationship [Member]
Acquired Definite-Lived Intangible Assets [Line Items]
Acquired definite-lived intangible assets, gross	6,930	0
Less: Accumulated amortization	(347)	0
Others [Member]
Acquired Definite-Lived Intangible Assets [Line Items]
Acquired definite-lived intangible assets, gross	8,926	3,666
Less: Accumulated amortization	(3,225)	(1,322)
Less: Impairment loss	$ (70)	$ (72)

Definite-Lived Intangible Assets, Accumulated Impairment Loss

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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

+ References

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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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