Annual report pursuant to Section 13 and 15(d)

Long-Term Debt - Key Terms of Credit Agreement (Details)

v3.20.4
Long-Term Debt - Key Terms of Credit Agreement (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2020
Mar. 20, 2020
Dec. 31, 2019
Long-Term Debt      
Amount outstanding $ 714,201    
Term Loan Facility      
Long-Term Debt      
Amount outstanding $ 288,750   $ 305,625
Senior Notes      
Long-Term Debt      
Interest rate (as a percent) 5.625%    
Amount outstanding $ 400,000   400,000
Equipment Notes      
Long-Term Debt      
Principal amount of debt     41,600
Amount outstanding 25,451   33,525
Equipment notes issued $ 0    
Debt term 5 years    
Equipment Notes | Minimum      
Long-Term Debt      
Interest rate (as a percent) 2.80%    
Equipment Notes | Maximum      
Long-Term Debt      
Interest rate (as a percent) 4.40%    
Revolving Facility      
Long-Term Debt      
Availability $ 450,000   $ 250,000
Amended Credit Agreement      
Long-Term Debt      
Additional term loan and/or revolver capacity available under incremental facility $ 300,000    
Scheduled maturity date Mar. 20, 2025    
Amended Credit Agreement | Minimum      
Long-Term Debt      
Commitment fee (as a percent) 0.15%    
Amended Credit Agreement | Maximum      
Long-Term Debt      
Commitment fee (as a percent) 0.275%    
Amended Credit Agreement | Term Loan Facility      
Long-Term Debt      
Availability $ 300,000 $ 300,000  
Amended Credit Agreement | Senior Notes      
Long-Term Debt      
Interest rate 5.625%    
Amended Credit Agreement | Senior Notes | Change in Control Scenario      
Long-Term Debt      
Redemption price as a percentage of principal 101.00%    
Amended Credit Agreement | Revolving Facility      
Long-Term Debt      
Availability $ 450,000 450,000  
Sublimit for issuance of letters of credit under Revolving Facility* 100,000 100,000  
Sublimit for swingline loans under Revolving Facility* $ 35,000 $ 35,000  
Interest rate 1.50%    
Amended Credit Agreement | Base Rate Borrowings | Minimum      
Long-Term Debt      
Applicable margin based on total leverage ratio 0.00%    
Amended Credit Agreement | Base Rate Borrowings | Maximum      
Long-Term Debt      
Applicable margin based on total leverage ratio 1.50%    
Amended Credit Agreement | LIBOR Rate Borrowings      
Long-Term Debt      
Interest rate floor (as a percent) 0.50%    
Amended Credit Agreement | LIBOR Rate Borrowings | Minimum      
Long-Term Debt      
Applicable margin based on total leverage ratio 1.00%    
Amended Credit Agreement | LIBOR Rate Borrowings | Maximum      
Long-Term Debt      
Applicable margin based on total leverage ratio 2.50%    
Federal Funds Rate | Amended Credit Agreement | Base Rate Borrowings      
Long-Term Debt      
Basis spread 0.50%    
LIBOR | Amended Credit Agreement | Base Rate Borrowings      
Long-Term Debt      
Basis spread 1.00%    
Maturity of the reference rate 1 month