Note 21 - Derivatives - Fair Value of Derivatives (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Coal Swap Contracts	$ 1,086	$ 0
Coal Swap Contracts	(53,290)	0
Coal Contract [Member]
Effect of Counterparty Netting, assets derivatives	(1,086)	0
Effect of Counterparty Netting, liabilities	1,086	(0)
Assets Derivatives, net	0	0
Liabilities, net	$ (52,204)	$ 0

Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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