Quarterly report pursuant to Section 13 or 15(d)

Line of Credit (Details)

v3.7.0.1
Line of Credit (Details)
Jun. 09, 2017
USD ($)
Jun. 30, 2017
USD ($)
Jun. 08, 2017
USD ($)
Line of Credit Facility [Line Items]      
Revolving credit facility $ 40,000,000.0    
Financial covenants, minimum current assets to current liabilities ratio 1.25    
Financial covenants, minimum net worth $ 230,000,000.0    
Financial covenants, percent of net income added to net worth requirement 50.00%    
Financial covenants, percent of proceeds from stock issuance added to net worth requirement 100.00%    
Financial covenant, maximum funded debt to tangible net worth ratio 0.50    
Total outstanding letters of credit     $ 4,600,000
Revolving credit facility, borrowings outstanding   $ 0  
Letter of Credit      
Line of Credit Facility [Line Items]      
Fees on undrawn borrowings 2.00%    
Revolving Credit Facility      
Line of Credit Facility [Line Items]      
Fees on undrawn borrowings 0.40%    
London Interbank Offered Rate (LIBOR) | Letter of Credit      
Line of Credit Facility [Line Items]      
Basis spread on variable rate 2.00%