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Long-Term Debt - Schedule of Notes Payable (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	Aug. 15, 2018
Debt Instrument [Line Items]
Long-term debt	$ 573,030	$ 583,826
Senior Notes
Debt Instrument [Line Items]
Long-term debt, gross			$ 575,000
2018 Revolving credit facility
Debt Instrument [Line Items]
Long-term debt, gross	136,462	146,000
Unamortized deferred financing and issuance costs - term loan	(4,248)	(4,673)
2018 Term Loan Facility
Debt Instrument [Line Items]
Long-term debt, gross	447,750	450,000
Unamortized deferred financing and issuance costs - term loan	$ (6,934)	$ (7,501)