Quarterly report pursuant to Section 13 or 15(d)

Fair Value - Carrying and Fair Value Amounts (Details)

v3.19.2
Fair Value - Carrying and Fair Value Amounts (Details) - USD ($)
Jun. 30, 2019
Dec. 31, 2018
Carrying Amount [Member] | Level 1 [Member]    
Financial Assets:    
Cash and cash equivalents $ 58,807,431 $ 69,287,177
Financial Liabilities:    
Unsecured convertible senior notes 69,113,639 112,777,271
Carrying Amount [Member] | Level 2 [Member]    
Financial Liabilities:    
Secured Credit Facilities 35,523,520 37,261,109
Carrying Amount [Member] | Level 3 [Member]    
Financial Assets:    
Financing notes receivable 1,309,217 1,300,000
Fair Value [Member] | Level 1 [Member]    
Financial Assets:    
Cash and cash equivalents 58,807,431 69,287,177
Financial Liabilities:    
Unsecured convertible senior notes 84,045,562 119,378,982
Fair Value [Member] | Level 2 [Member]    
Financial Liabilities:    
Secured Credit Facilities 35,523,520 37,261,109
Fair Value [Member] | Level 3 [Member]    
Financial Assets:    
Financing notes receivable $ 1,309,217 $ 1,300,000