Note 12 - Long-term Debt - Long-term Debt (Details) - USD ($) $ in Thousands		Mar. 31, 2022	Dec. 31, 2021
Long-Term Debt, Total		$ 573,997	$ 604,641
Unamortized discount		7,751	9,111
Less: Amounts Due in One Year*	[1]	39,095	36,589
Long-Term Debt		534,902	568,052
MEDCO Revenue Bonds in Series Due September 2025 at 5.75% [Member]
Long-Term Debt, Total		102,865	102,865
PEDFA Solid Waste Disposal Revenue Bonds [Member]
Long-Term Debt, Total		75,000	75,000
Term Loan A Facility [Member]
Long-Term Debt, Total		35,000	41,250
Other Asset Backed Financing [Member]
Long-Term Debt, Total		1,895	2,082
Advance Royalty Commitments [Member]
Long-Term Debt, Total		4,858	4,858
Loans Payable [Member] | Term Loan B Facility [Member]
Long-Term Debt, Total		238,023	238,590
Unamortized discount		567	687
Senior Notes [Member] | Senior Secured Second Lien Notes due 2025 [Member]
Long-Term Debt, Total		$ 124,107	$ 149,107

[1] Excludes current portion of Finance Lease Obligations of $23,226 and $20,743 at March 31, 2022 and December 31, 2021, respectively.