v3.8.0.1
Debt - Schedule of Long-Term Debt (Details) - USD ($)
$ in Thousands
Mar. 31, 2018
Dec. 31, 2017
Debt Instrument [Line Items]    
Capital lease obligation (6.8%) $ 528 $ 569
Total debt and capital lease obligation 996,392 999,188
Less: Amounts due within one year (11,268) (11,268)
Long-term portion 985,124 987,920
Term Loan | Third First Lien Term Loan (3.9% as of March 31, 2018)    
Debt Instrument [Line Items]    
Principal 991,278 993,762
Unamortized debt premium and issuance costs 4,586 4,857
Long-term debt $ 995,864 $ 998,619
Effective rate 3.90%  
Capital lease obligation    
Debt Instrument [Line Items]    
Effective rate 6.80%