Long-Term Debt - Schedule Of Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Aug. 14, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Principal amount	$ 404,732
Unamortized debt discounts	(45,692)		$ (22,540)
Unamortized debt issuance costs	(9,477)		(7,753)
Total debt	349,563		405,853
Less current maturities	(90,651)		(99,731)
Long-term debt	258,912		306,122
Term Loan Maturing December 2021
Debt Instrument [Line Items]
Principal amount	29,750		33,250
Unamortized debt discounts	0
Unamortized debt issuance costs	(191)
Total debt	29,559
Less current maturities	(29,559)
Long-term debt	0
Convertible Senior Notes Maturing May 2022
Debt Instrument [Line Items]
Principal amount	35,000		125,000
Unamortized debt discounts	(1,325)		(8,000)
Unamortized debt issuance costs	(198)
Total debt	33,477
Less current maturities	0
Long-term debt	33,477
Convertible Senior Notes Maturing September 2023
Debt Instrument [Line Items]
Principal amount	30,000		125,000
Unamortized debt discounts	(2,651)		(14,500)
Unamortized debt issuance costs	(427)
Total debt	26,922
Less current maturities	0
Long-term debt	26,922
Convertible Senior Notes Maturing February 2026
Debt Instrument [Line Items]
Principal amount	200,000	$ 200,000	0
Unamortized debt discounts	(41,716)
Unamortized debt issuance costs	(5,572)
Total debt	152,712
Less current maturities	0
Long-term debt	152,712
MARAD Debt Maturing February 2027
Debt Instrument [Line Items]
Principal amount	56,410		63,610
Unamortized debt discounts	0
Unamortized debt issuance costs	(3,049)
Total debt	53,361
Less current maturities	(7,560)
Long-term debt	45,801
Nordea Q5000 Loan Maturing January 2021
Debt Instrument [Line Items]
Principal amount	53,572		$ 89,286
Unamortized debt discounts	0
Unamortized debt issuance costs	(40)
Total debt	53,532
Less current maturities	(53,532)
Long-term debt	$ 0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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