Debt - Schedule of Long-term Debt (Details) - Senior Secured Notes - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Debt instrument, unamortized discount	$ 12,076	$ 13,576
Debt instrument, imputed interest rate	5.80%	5.80%
Long-term debt	$ 522,524	$ 525,074
Less current maturities	(3,185)	(3,193)
Total long-term debt	$ 519,339	$ 521,881

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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