Long-Term Debt - Maturities Of Long-Term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Less than one year	$ 38,539
One to two years	8,965
Two to three years	209,412
Three to four years	9,881
Gross debt	266,797	$ 270,913
Unamortized debt issuance costs	(6,337)
Total debt	260,460
Less: current maturities	(38,452)	(38,200)
Long-term debt	222,008	225,875
2023 Notes (mature September 2023)
Debt Instrument [Line Items]
Less than one year	30,000
Gross debt	30,000	30,000
Unamortized debt issuance costs	(87)
Total debt	29,913
Less: current maturities	(29,913)
2026 Notes (mature February 2026)
Debt Instrument [Line Items]
Two to three years	200,000
Gross debt	200,000	200,000
Unamortized debt issuance costs	(4,299)
Total debt	195,701
Long-term debt	195,701
MARAD Debt (matures February 2027)
Debt Instrument [Line Items]
Less than one year	8,539
One to two years	8,965
Two to three years	9,412
Three to four years	9,881
Gross debt	36,797	$ 40,913
Unamortized debt issuance costs	(1,951)
Total debt	34,846
Less: current maturities	(8,539)
Long-term debt	$ 26,307

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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Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

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