Note 2 - Basis of Presentation and Summary of Significant Accounting Policies - Summary of Other Property and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Other property and equipment, net	$ 3,518	$ 3,572
Land [Member]
Other property and equipment, net	2,091	2,139
Transportation Equipment [Member]
Other property and equipment, net	700	689
Building [Member]
Other property and equipment, net	523	530
Leasehold Improvements [Member]
Other property and equipment, net	201	209
Field Equipment [Member]
Other property and equipment, net	3	4
Furniture and Fixtures [Member]
Other property and equipment, net	$ 0	$ 1