Note 15 - Merom Acquisition (Details Textual) - USD ($) $ in Millions	Feb. 14, 2022	May 31, 2023
Capacity Payment Reductions		$ 7.5
Merom Acquisition [Member]
Capacity Payment Reductions	$ 15.0
Purchase Obligation, Total	7.2
Business Acquisition, Purchase of Coal Inventory	17.0
Business Acquisition, Purchase of Coal Inventory, Initial Payment	5.4
Business Acquisition, Transaction Costs	$ 2.9