Annual report pursuant to Section 13 and 15(d)

Subsequent Events (Details)

v3.8.0.1
Subsequent Events (Details)
12 Months Ended
Feb. 28, 2018
USD ($)
Dec. 31, 2017
USD ($)
Maximum    
Subsequent Event [Line Items]    
Senior leverage ratio   3.00
Revolving Credit Facility | Line of Credit | Maximum    
Subsequent Event [Line Items]    
Senior leverage ratio   3.00
Revolving Credit Facility | Line of Credit | Subsequent Event | Maximum    
Subsequent Event [Line Items]    
Senior leverage ratio 3.50  
Revolving Credit Facility | Line of Credit | Senior Credit Facility    
Subsequent Event [Line Items]    
Maximum borrowing capacity   $ 200,000,000
Revolving Credit Facility | Line of Credit | Senior Credit Facility | Subsequent Event    
Subsequent Event [Line Items]    
Maximum borrowing capacity $ 300,000,000