Note 14 - Derivatives - Fair Value of Derivatives (Details) - Coal Contract [Member] - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Coal Swap Contracts	$ 75,132	$ 1,086
Coal Swap Contracts	(275,317)	(53,290)
Effect of Counterparty Netting, assets derivatives	(75,132)	(1,086)
Effect of Counterparty Netting, liabilities	75,132	1,086
Assets Derivatives, net	0	0
Liabilities, net	$ (200,185)	$ (52,204)

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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