Derivatives - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2022
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain (loss) on derivatives and commodity contracts	$ (5,571)	$ 96,331
Coal Contract
Derivative Instruments, Gain (Loss) [Line Items]
Realized gain (loss), investment and derivative	(73,923)	(160,175)
Unrealized gain (loss) on derivatives and commodity contracts	$ (5,571)	$ 96,331

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, before tax, of realized gain (loss) on investment and derivative, classified as operating. Investment includes, but is not limited to, debt and equity securities, security sold short, real estate, and commodity.

+ References

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-Topic 946
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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of open derivatives, commodity, or energy contracts, held at each balance sheet date, that was included in earnings for the period.

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