Note 7 - Revenue - Coal Operations (Details) - Coal Operations [Member] - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Revenues	$ 32,801	$ 88,574	$ 82,431	$ 183,176
INDIANA
Revenues	15,048	34,214	33,152	83,650
Florida, North Carolina, Alabama and Georgia [Member]
Revenues	$ 17,753	$ 54,360	$ 49,279	$ 99,526

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details