Debt and Capital Lease Obligations - Revolving Credit Facility (Details) - USD ($)
 3 Months Ended
Mar. 31, 2017
Apr. 30, 2018
Jan. 31, 2018
Line of Credit Facility [Line Items]      
Minimum cash recovery percentage   4.45%  
Original Principal Amount   $ 1,094,276,000  
Deferred debt issuance costs   7,063,000 $ 8,886,000
Revolving Credit Facility [Member]      
Line of Credit Facility [Line Items]      
Deferred debt issuance costs   $ 4,400,000 $ 5,200,000
Line of Credit [Member] | Revolving Credit Facility [Member]      
Line of Credit Facility [Line Items]      
Maximum capacity extended under credit facility $ 750,000,000    
Unused capacity fee percentage 0.75%    
Weighted-average interest rate   7.40%  
Restrictions on payment of dividends, amount free from restriction   $ 64,700,000  
Line of Credit [Member] | Revolving Credit Facility [Member] | Minimum [Member]      
Line of Credit Facility [Line Items]      
Unused capacity fee percentage   0.25%  
Line of Credit [Member] | Revolving Credit Facility [Member] | Maximum [Member]      
Line of Credit Facility [Line Items]      
Unused capacity fee percentage   0.75%  
Line of Credit [Member] | Revolving Credit Facility [Member] | LIBOR [Member]      
Line of Credit Facility [Line Items]      
Variable basis spread   1.00%  
Line of Credit [Member] | Revolving Credit Facility [Member] | Alternate Base Rate [Member] | Minimum [Member]      
Line of Credit Facility [Line Items]      
Variable basis spread   1.75%  
Line of Credit [Member] | Revolving Credit Facility [Member] | Alternate Base Rate [Member] | Maximum [Member]      
Line of Credit Facility [Line Items]      
Variable basis spread   2.25%  
Line of Credit [Member] | Revolving Credit Facility [Member] | Federal Funds Rate [Member]      
Line of Credit Facility [Line Items]      
Variable basis spread   0.50%  
Line of Credit [Member] | Letter of Credit [Member]      
Line of Credit Facility [Line Items]      
Original Principal Amount   $ 40,000,000.0  
Revolving Credit Facility [Member]      
Line of Credit Facility [Line Items]      
Sub-facility for letters of credit   2,800,000  
Available borrowing capacity   233,500,000  
Additional remaining borrowing capacity   $ 366,200,000  
Revolving Credit Facility [Member] | LIBOR [Member] | Minimum [Member]      
Line of Credit Facility [Line Items]      
Variable basis spread   2.75%  
Revolving Credit Facility [Member] | LIBOR [Member] | Maximum [Member]      
Line of Credit Facility [Line Items]      
Variable basis spread   3.25%