Long-Term Debt - Maturities Of Long-Term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Less than one year	$ 38,333
One to two years	8,749
Two to three years	9,186
Three to four years	209,644
Four to five years	5,001
Gross debt	270,913	$ 313,850
Unamortized debt issuance costs	(7,332)
Total debt	263,581
Less: current maturities	(38,154)	(42,873)
Long-term debt	225,427	262,137
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	(179)
Total debt	29,821
Less: current maturities	(29,821)
2026 Notes (mature February 2026)
Debt Instrument [Line Items]
Three to four years	200,000
Gross debt	200,000	200,000
Unamortized debt issuance costs	(4,958)
Total debt	195,042
Long-term debt	195,042
MARAD Debt (matures February 2027)
Debt Instrument [Line Items]
Less than one year	8,333
One to two years	8,749
Two to three years	9,186
Three to four years	9,644
Four to five years	5,001
Gross debt	40,913	$ 48,850
Unamortized debt issuance costs	(2,195)
Total debt	38,718
Less: current maturities	(8,333)
Long-term debt	$ 30,385

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 fifth 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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