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Debt and Debt Issuance Costs - Schedule of Debt (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Feb. 15, 2018
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ (21,081,000)	$ (15,585,000)
Finance Lease, Liability	3,540,000
Long-term debt	700,459,000	399,415,000
Finance lease, liability, current	$ 3,300,000
Senior Notes \| 6.25% Senior Notes
Debt Instrument [Line Items]
Stated interest rate	6.25%		6.25%
Long-term debt, gross	$ 300,000,000	300,000,000	$ 300,000,000.0
Senior Notes \| 7.75% Senior Notes
Debt Instrument [Line Items]
Long-term debt, gross	300,000,000	0
Convertible Notes
Debt Instrument [Line Items]
Long-term debt, gross	0	115,000,000
Revolving credit facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt, gross	$ 118,000,000	$ 0