XML 89 R51.htm IDEA: XBRL DOCUMENT v2.4.0.6
Accounting Policies (Fair Value of Financial Instruments) (Details) (USD $)
Mar. 31, 2013
Dec. 31, 2012
Mar. 31, 2012
Dec. 31, 2011
Cash and cash equivalents $ 212,665 $ 430,746 $ 11,632 $ 214,684
Restricted cash 19,149,140 19,044,294    
Warrants 13,715 7,340    
Marketable investment securities
       
Cash and cash equivalents 3,803,966 1,131,109    
Restricted cash 16,410,824 15,507,408    
Marketable investment securities
       
Cash and cash equivalents 0 0    
Restricted cash 0 0    
Warrants 327,763 850,841    
Marketable investment securities
       
Cash and cash equivalents 0 0    
Restricted cash 0 0    
Warrants $ 0 $ 0