Note 4 - Property, Plant and Equipment - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Property, plant and equipment, net	$ 1,713,796	$ 218,646
Property, plant and equipment, net	1,713,796	218,646
Computer Equipment [Member]
Property, plant and equipment, gross	779	780
Furniture and Fixtures [Member]
Property, plant and equipment, gross	610	610
Vehicles [Member]
Property, plant and equipment, gross	166	0
Leasehold Improvements [Member]
Property, plant and equipment, gross	3,086	101
Excluding Construction in Progress [Member]
Property, plant and equipment, gross	4,641	1,491
Less: accumulated depreciation	(1,123)	(1,006)
Property, plant and equipment, net	3,518	485
Property, plant and equipment, net	3,518	485
Construction in Progress [Member]
Property, plant and equipment, gross	1,710,278	218,161
Construction in Progress [Member] | Rio Grande [Member]
Property, plant and equipment, gross	1,710,278	197,144
Construction in Progress [Member] | Rio Bravo [Member]
Property, plant and equipment, gross	$ 0	$ 21,017