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Long-Term Debt - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Apr. 30, 2021	Nov. 30, 2017
Debt Instrument [Line Items]
Less: Unamortized Debt Issuance Costs	$ (2,673)	$ (3,721)
Principal amount	257,736	346,851
Less: amounts due in one year	(4,759)	(4,741)
Long-Term Debt	252,977	342,110
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%
PEDFA Solid Waste Disposal Revenue Bonds
Debt Instrument [Line Items]
Long-term debt, gross	$ 75,000	75,000
Stated interest rate percentage	9.00%		900.00%
Other Asset Backed Financing
Debt Instrument [Line Items]
Long-term debt, gross	$ 2,165	2,400
Advance Royalty Commitments
Debt Instrument [Line Items]
Long-term debt, gross	$ 7,716	$ 7,716
Weighted average interest rate	8.09%	8.09%
Senior Notes \| Senior Secured Second Lien Notes due 2025
Debt Instrument [Line Items]
Long-term debt, gross	$ 49,107	$ 99,107
Stated interest rate percentage	11.00%			11.00%
Loans Payable \| Revolving Credit Facility
Debt Instrument [Line Items]
Finance lease, liability, current	$ 19,821	24,105
Loans Payable \| Term Loan B Facility
Debt Instrument [Line Items]
Long-term debt, gross	23,556	63,484
Less: Unamortized Debt Issuance Costs	(34)	(106)
Principal amount	$ 23,590	$ 63,590
Weighted average interest rate	11.50%	8.92%