Annual report pursuant to Section 13 and 15(d)

Long-Term Debt - Narrative (Details)

v3.8.0.1
Long-Term Debt - Narrative (Details)
12 Months Ended
Apr. 01, 2016
USD ($)
Dec. 31, 2017
USD ($)
Dec. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Debt Instrument [Line Items]        
Proceeds from revolving credit facility   $ 90,000,000 $ 110,000,000 $ 0
Cash distribution to former parent $ 50,000,000 $ 0 $ 50,000,000 $ 0
Covenant terms, minimum fixed charge coverage ratio   1.0    
Other Noncurrent Assets        
Debt Instrument [Line Items]        
Financing and related costs 1,400,000      
Revolving Credit Facility        
Debt Instrument [Line Items]        
Proceeds from revolving credit facility 100,000,000      
Line of Credit | Revolving Credit Facility        
Debt Instrument [Line Items]        
Maximum borrowing capacity $ 225,000,000      
Debt instrument term 5 years      
Credit facility outstanding   $ 85,000,000    
Letters of credit outstanding   $ 3,000,000    
Unused capacity commitment fee (percent)   0.25%    
Line of Credit | Revolving Credit Facility | London Interbank Offered Rate (LIBOR)        
Debt Instrument [Line Items]        
Basis spread on variable rate   1.50%    
Line of Credit | Revolving Credit Facility | Base Rate        
Debt Instrument [Line Items]        
Basis spread on variable rate   1.625%    
Line of Credit | Standby Letters of Credit        
Debt Instrument [Line Items]        
Maximum borrowing capacity $ 50,000,000      
Interest rate   3.07%