Long-Term Debt - Schedule of Notes Payable (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term debt	$ 570,348	$ 583,827
2018 Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt, gross	134,306	146,000
Unamortized deferred financing and issuance costs - term loan	(3,933)	(4,673)
2018 Term Loan Facility
Debt Instrument [Line Items]
Long-term debt, gross	446,625	450,000
Unamortized deferred financing and issuance costs - term loan	$ (6,650)	$ (7,500)