CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - $ / shares	Mar. 31, 2017	Dec. 31, 2016
Class A Ordinary Shares [Member]
Shareholders' Equity
Ordinary shares, par value (in dollars per share)	$ 0.01	$ 0.01
Ordinary shares, shares issued (in shares)	66,966,397	65,998,306
Ordinary shares, shares outstanding (in shares)	66,241,691	65,165,672
Class B Ordinary Shares [Member]
Shareholders' Equity
Ordinary shares, par value (in dollars per share)	$ 0.01	$ 0.01
Ordinary shares, shares issued (in shares)	51,154,280	51,154,280
Ordinary shares, shares outstanding (in shares)	51,154,280	51,154,280

Face amount or stated value per share of common stock.

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

+ Details

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

+ Details

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- References

No definition available.

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