Quarterly report pursuant to Section 13 or 15(d)

Debt (Details)

v3.10.0.1
Debt (Details)
 6 Months Ended
Jun. 30, 2015
USD ($)
Nov. 25, 2014
USD ($)
Jun. 30, 2018
USD ($)
Dec. 31, 2017
USD ($)
Line of Credit Facility [Line Items]        
Outstanding borrowing under the credit facility     $ 0 $ 99,900,000
Revolving Credit Facility        
Line of Credit Facility [Line Items]        
Maximum borrowing capacity   $ 170,000,000.0    
Remaining borrowing capacity     $ 162,700,000 62,800,000
Maximum leverage ratio     4.0  
Debt covenant, minimum availability required     $ 10,000,000  
Letter of Credit        
Line of Credit Facility [Line Items]        
Remaining borrowing capacity     $ 6,500,000 $ 6,500,000
London Interbank Offered Rate (LIBOR) | Revolving Credit Facility        
Line of Credit Facility [Line Items]        
Increments of debt that can be converted   $ 500,000    
Minimum | Revolving Credit Facility        
Line of Credit Facility [Line Items]        
Interest coverage rate     3.0  
Minimum | London Interbank Offered Rate (LIBOR) | Revolving Credit Facility        
Line of Credit Facility [Line Items]        
Basis spread on variable rate   1.50%    
Maximum | London Interbank Offered Rate (LIBOR) | Revolving Credit Facility        
Line of Credit Facility [Line Items]        
Basis spread on variable rate   3.00%    
Sturgeon Acquisitions LLC | Revolving Credit Facility        
Line of Credit Facility [Line Items]        
Maximum borrowing capacity $ 25,000,000.0      
Basis spread on variable rate 2.00%      
Debt instrument, term 3 years      
Sturgeon Acquisitions LLC | London Interbank Offered Rate (LIBOR) | Revolving Credit Facility        
Line of Credit Facility [Line Items]        
Basis spread on variable rate 3.00%      
Sturgeon Acquisitions LLC | Federal Fund Open Rate | Revolving Credit Facility        
Line of Credit Facility [Line Items]        
Basis spread on variable rate 0.50%