Annual report pursuant to Section 13 and 15(d)

Debt (Details)

v3.6.0.2
Debt (Details)
 12 Months Ended
Dec. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Nov. 25, 2014
USD ($)
Line of Credit Facility [Line Items]      
Long-term debt $ 0 $ 95,000,000  
Revolving Credit Facility      
Line of Credit Facility [Line Items]      
Maximum borrowing capacity     $ 170,000,000.0
Long-term debt   95,000,000  
Remaining borrowing capacity $ 146,181,002 $ 44,619,551  
Maximum leverage ratio 4.0    
Debt covenant, minimum availability required $ 10,000,000    
Revolving Credit Facility | Minimum      
Line of Credit Facility [Line Items]      
Interest coverage ratio 3.0    
Revolving Credit Facility | London Interbank Offered Rate (LIBOR)      
Line of Credit Facility [Line Items]      
Increments of debt that can be converted $ 500,000    
Debt instrument, interest rate, percent   3.04%  
Revolving Credit Facility | London Interbank Offered Rate (LIBOR) | Minimum      
Line of Credit Facility [Line Items]      
Basis spread on variable rate, percent 1.50%    
Revolving Credit Facility | London Interbank Offered Rate (LIBOR) | Maximum      
Line of Credit Facility [Line Items]      
Basis spread on variable rate, percent 3.00%