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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Contractual interest rate for funds borrowed, under the debt agreement.

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Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

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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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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Long-term Debt - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Apr. 30, 2021	Dec. 31, 2017	Nov. 30, 2017
Debt Instrument [Line Items]
Long-term debt, gross	$ 350,678
Less: Unamortized Debt Issuance Costs	(3,721)	$ (9,111)
Principal amount	346,851	604,641
Less: amounts due in one year	(4,741)	(36,589)
Long-Term Debt	342,110	568,052
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%		900.00%
Term Loan A Facility
Debt Instrument [Line Items]
Long-term debt, gross	$ 0	$ 41,250
Weighted average interest rate		5.25%
Other Asset Backed Financing
Debt Instrument [Line Items]
Long-term debt, gross	2,400	$ 2,082
Advance Royalty Commitments
Debt Instrument [Line Items]
Long-term debt, gross	$ 7,716	$ 4,858
Weighted average interest rate	8.09%	8.01%
Loans Payable \| Revolving Credit Facility
Debt Instrument [Line Items]
Current portion of finance lease obligations	$ 24,105	$ 20,743
Loans Payable \| Term Loan B Facility
Debt Instrument [Line Items]
Long-term debt, gross	63,484	238,590
Less: Unamortized Debt Issuance Costs	(106)	(687)
Principal amount	$ 63,590	$ 239,277
Weighted average interest rate	8.92%	4.61%
Senior Notes \| Senior Secured Second Lien Notes due 2025
Debt Instrument [Line Items]
Long-term debt, gross	$ 99,107	$ 149,107
Stated interest rate percentage	11.00%	11.00%		11.00%	11.00%