Long-Term Debt - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023	Apr. 30, 2021
Debt Instrument [Line Items]
Less: Unamortized Debt Issuance Costs	$ (1,449)	$ (1,686)
Principal amount	183,247	183,520
Less: amounts due in one year	(1,238)	(1,635)
Long-Term Debt	182,009	181,885
MEDCO Revenue Bonds in Series Due September 2025 at 5.75%
Debt Instrument [Line Items]
Long-term debt, gross	$ 102,865	$ 102,865
Stated interest rate percentage	5.75%	5.75%
PEDFA Solid Waste Disposal Revenue Bonds
Debt Instrument [Line Items]
Long-term debt, gross	$ 75,000	$ 75,000
Stated interest rate percentage	9.00%	9.00%	9.00%
Advance Royalty Commitments
Debt Instrument [Line Items]
Long-term debt, gross	$ 5,922	$ 5,922
Weighted average interest rate	8.80%	8.80%
Other Debt Arrangements
Debt Instrument [Line Items]
Long-term debt, gross	$ 909	$ 1,419
Loans Payable \| Revolving Credit Facility
Debt Instrument [Line Items]
Finance lease, liability, current	$ 4,774	$ 9,471

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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