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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- Definition

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

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Weighted average interest rate of debt outstanding.

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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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Note 13 - Long-term Debt - Long-term Debt (Details) (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2021	Apr. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2017	Nov. 30, 2017
Principal Amount	$ 614,439
Unamortized discount	$ 9,111		$ 9,921
MEDCO Revenue Bonds in Series Due September 2025 at 5.75% [Member]
Debt Instrument, Interest Rate, Stated Percentage	5.75%		5.75%
PEDFA Solid Waste Disposal Revenue Bonds [Member]
Debt Instrument, Interest Rate, Stated Percentage	9.00%	9.00%
Term Loan A Facility [Member]
Debt, Weighted Average Interest Rate	5.25%		5.50%
Advance Royalty Commitments [Member]
Debt, Weighted Average Interest Rate	8.01%		13.68%
Loans Payable [Member] \| Term Loan B Facility [Member]
Principal Amount	$ 239,277		$ 270,188
Unamortized discount	$ 687		$ 938
Debt, Weighted Average Interest Rate	4.61%		4.65%
Senior Notes [Member] \| Senior Secured Second Lien Notes due 2025 [Member]
Debt Instrument, Interest Rate, Stated Percentage	11.00%		11.00%	11.00%	11.00%	11.00%