Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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This element represents the fair value of the noncontrolling interest in the acquiree at the acquisition date.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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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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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The amount of tangible assets recognized as of the acquisition date.

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Represents the amount of consideration for transfer of equity interest of an acquiree to the entity from its parent.

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Number of venture funds controlled and transferred by parent.

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Represents the percentage of equity interest of an acquiree transferred to the entity from its parent.

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Acquisitions - Gametree (Details) $ in Thousands		1 Months Ended
Acquisitions - Gametree (Details) $ in Thousands	Jun. 30, 2015 USD ($) fund	Oct. 31, 2014 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Acquisitions
Goodwill			$ 10,266	$ 11,117	$ 11,652
Transfer of Equity Interest in Weibo Funds \| SINA
Acquisitions
Number of funds acquired \| fund	2
Consideration for transfer of equity interest	$ 22,000
Transfer of Equity Interest in Weibo Funds \| SINA \| Weibo Funds, one
Acquisitions
Percentage of equity interest transferred to Group	55.00%
Transfer of Equity Interest in Weibo Funds \| SINA \| Weibo Funds, two
Acquisitions
Percentage of equity interest transferred to Group	85.00%
Gametree
Acquisitions
Cash consideration		$ 3,062
Equity interest acquired (as a percent)		84.00%
Non-controlling interests		$ 292
Total consideration		3,354
Tangible assets		1,518
Identifiable intangible assets acquired		1,688
Liabilities assumed		(3,692)
Goodwill		3,840
Total consideration		$ 3,354
Gametree \| Game platform technology
Acquisitions
Estimated useful life of identifiable intangible assets acquired		4 years 3 months 18 days
Identifiable intangible assets acquired		$ 1,700