Summary of Significant Accounting Policies- Restricted Cash (Details) - USD ($) $ in Thousands  | 
Mar. 31, 2016  | 
Dec. 31, 2015  | 
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| Accounting Policies [Abstract] | ||
| Restricted cash non-current | $ 16,672 | $ 13,515 | 
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- References No definition available. 
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- Definition Cash and equivalents whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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