Derivatives - Schedule of Derivative Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Asset Derivatives
Effect of Counterparty Netting	$ 0	$ (6,024)
Net derivative assets	0	0
Liability Derivatives
Effect of Counterparty Netting	0	6,024
Net derivative liabilities	0	(15,142)
Coal Contract
Asset Derivatives
Coal swap contract asset derivatives	0	6,024
Liability Derivatives
Coal swap contract liability derivatives	$ 0	$ (21,166)

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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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Fair value, after the effects of master netting arrangements, of a 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, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, before effects of master netting arrangements, of a financial liability or 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. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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