Annual report pursuant to Section 13 and 15(d)

Debt - Convertible Debt Information (Details)

v3.8.0.1
Debt - Convertible Debt Information (Details) - USD ($)
3 Months Ended 12 Months Ended
May 23, 2016
Jun. 29, 2015
Dec. 31, 2017
Sep. 30, 2017
Jun. 30, 2017
Mar. 31, 2017
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Debt Instrument [Line Items]                  
Repurchases of convertible debt $ 1,000,000           $ 0 $ 899,960 $ 0
Gain on extinguishment of debt     $ (102,500) $ (234,433) $ 0 $ 0 (336,933) 0 $ 0
Convertible Senior Notes Due 2020 [Member]                  
Debt Instrument [Line Items]                  
Amount of underwriter's discount     1,847,254       1,847,254 2,586,166  
Convertible Debt [Member]                  
Debt Instrument [Line Items]                  
Gain on extinguishment of debt               $ 72,000  
Amount of underwriter's discount     3,700,000       3,700,000    
Deferred debt financing costs, net     241,000       $ 241,000    
Effective percentage             7.70% 7.70% 7.70%
Convertible Debt [Member] | Convertible Senior Notes Due 2020 [Member]                  
Debt Instrument [Line Items]                  
Face amount   $ 115,000,000.0 $ 115,000,000       $ 115,000,000    
Interest Rate   7.00% 7.00%       7.00% 7.00%  
Shares issued (in shares)   30.3030              
Principal amount   $ 1,000              
Conversion price (in dollars per share)   $ 33.00              
Percentage of principal amount redeemed   100.00%