Note 2 - Basis of Presentation and Summary of Significant Accounting Policies - Other Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Other property and equipment, net	$ 3,201	$ 3,572
Land [Member]
Other property and equipment, net	1,869	2,139
Transportation Equipment [Member]
Other property and equipment, net	620	689
Building [Member]
Other property and equipment, net	516	530
Leasehold Improvements [Member]
Other property and equipment, net	193	209
Field Equipment [Member]
Other property and equipment, net	2	4
Furniture and Fixtures [Member]
Other property and equipment, net	$ 1	$ 1