Quarterly report pursuant to Section 13 or 15(d)

Fair Value - Carrying and Fair Value Amounts (Details)

v3.19.3
Fair Value - Carrying and Fair Value Amounts (Details) - USD ($)
Sep. 30, 2019
Aug. 12, 2019
Dec. 31, 2018
Jun. 29, 2015
Convertible Debt | 7.00% Unsecured Convertible Senior Notes        
Financial Liabilities:        
Interest rate percentage 7.00%   7.00% 7.00%
Convertible Debt | 5.875% Unsecured Convertible Senior Notes        
Financial Liabilities:        
Interest rate percentage 5.875% 5.875% 0.00%  
Carrying Amount | Level 1        
Financial Assets:        
Cash and cash equivalents $ 120,430,110   $ 69,287,177  
Carrying Amount | Level 1 | 7.00% Unsecured Convertible Senior Notes        
Financial Liabilities:        
Unsecured convertible senior notes 5,497,251   112,777,271  
Carrying Amount | Level 2        
Financial Liabilities:        
Secured credit facilities 34,654,725   37,261,109  
Carrying Amount | Level 2 | 5.875% Unsecured Convertible Senior Notes        
Financial Liabilities:        
Unsecured convertible senior notes 116,086,037   0  
Carrying Amount | Level 3        
Financial Assets:        
Financing notes receivable 1,267,500   1,300,000  
Fair Value | Level 1        
Financial Assets:        
Cash and cash equivalents 120,430,110   69,287,177  
Fair Value | Level 1 | 7.00% Unsecured Convertible Senior Notes        
Financial Liabilities:        
Unsecured convertible senior notes 7,937,160   119,378,982  
Fair Value | Level 2        
Financial Liabilities:        
Secured credit facilities 34,654,725   37,261,109  
Fair Value | Level 2 | 5.875% Unsecured Convertible Senior Notes        
Financial Liabilities:        
Unsecured convertible senior notes 126,430,800   0  
Fair Value | Level 3        
Financial Assets:        
Financing notes receivable $ 1,267,500   $ 1,300,000