XML 42 R31.htm IDEA: XBRL DOCUMENT v3.10.0.1
Debt - Additional Information (Details) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2018
Sep. 30, 2017
Jun. 30, 2017
Jun. 30, 2018
Jun. 30, 2017
Dec. 31, 2017
Debt Instrument [Line Items]            
Borrowings under credit facilities       $ 6,000,000 $ 2,000,000  
Repayments of borrowings       2,000,000 1,500,000  
Debt outstanding $ 4,000,000     4,000,000   $ 0
Interest expense and fees 100,000   $ 200,000 200,000 $ 400,000  
Maximum            
Debt Instrument [Line Items]            
Accrued interest $ 100,000     $ 100,000   $ 100,000
New Revolving Facility            
Debt Instrument [Line Items]            
Debt instrument, face amount   $ 30,000,000        
Increase in credit facility   $ 10,000,000        
Line of credit facility, maturity month and year   2020-09        
New Revolving Facility | Minimum            
Debt Instrument [Line Items]            
Debt instrument reduction in unused rate       0.25%    
Debt instrument reduction in total rate       2.00%    
New Revolving Facility | Minimum | Base Rate            
Debt Instrument [Line Items]            
Line of credit facility, applicable margin   0.75%        
New Revolving Facility | Minimum | LIBOR            
Debt Instrument [Line Items]            
Line of credit facility, applicable margin   1.75%        
New Revolving Facility | Maximum            
Debt Instrument [Line Items]            
Debt instrument reduction in unused rate       0.75%    
Debt instrument reduction in total rate       2.50%    
New Revolving Facility | Maximum | Base Rate            
Debt Instrument [Line Items]            
Line of credit facility, applicable margin   1.25%        
New Revolving Facility | Maximum | LIBOR            
Debt Instrument [Line Items]            
Line of credit facility, applicable margin   2.25%