Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares  | 
Sep. 30, 2016  | 
Dec. 31, 2015  | 
|---|---|---|
| Statement Of Financial Position [Abstract] | ||
| Common shares, par value | $ 0.001 | $ 0.001 | 
| Common shares, shares authorized | 1,000,000,000 | 1,000,000,000 | 
| Common shares, shares outstanding | 93,100,000 | 92,700,000 | 
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- Definition Face amount or stated value per share of common stock. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
- Definition The maximum number of common shares permitted to be issued by an entity's charter and bylaws. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
- References No definition available. 
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