| 
           Restricted Cash (Details) (USD $) 
        In Thousands, unless otherwise specified  | 
        
           Mar. 31, 2014 
         | 
        
           Dec. 31, 2013 
         | 
      
|---|---|---|
| Non-current restricted cash | $ 5,055 | $ 5,055 | 
| 
           Cash On Deposit At Banks [Member] 
         | 
        ||
| Non-current restricted cash | 4,955 | 4,955 | 
| 
           Money Market Funds [Member] 
         | 
        ||
| Non-current restricted cash | $ 100 | $ 100 | 
| X | ||||||||||
| 
             
- 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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