Note 10 - Related Party Transactions - HighPeak II Results of Operations (Details) - USD ($) $ in Thousands	1 Months Ended	2 Months Ended	3 Months Ended					8 Months Ended	9 Months Ended
	Sep. 30, 2020	Aug. 21, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Aug. 21, 2020	Sep. 30, 2019
Total operating revenues	$ 4,834	$ 2,656			$ 1,443			$ 8,223	$ 4,257
Production and ad valorem taxes	257	164			80			566	261
Exploration and abandonment	66				159			4	2,817
Accretion of discount	15	20			14			89	38
Total operating costs and expenses	18,660	2,712			2,452			16,754	10,090
Loss from operations	(13,826)	(56)			(1,009)			(8,531)	(5,833)
Net loss	(11,516)	(56)	$ (4,147)	$ (80,831)	(1,009)	$ (1,411)	$ (3,413)	(85,034)	(5,833)
Crude Oil Sales [Member]
Total operating revenues	4,787	2,607			1,419			8,069	4,154
Natural Gas and NGL Sales [Member]
Total operating revenues	$ 47	$ 49			24			$ 154	103
HighPeak II [Member]
Total operating revenues					555				942
Oil and natural gas production					488				1,190
Production and ad valorem taxes					35				59
Exploration and abandonment					48				756
Depletion, depreciation and amortization					445				650
Accretion of discount					30				86
General and administrative					964				2,891
Total operating costs and expenses					3,132				6,754
Loss from operations					(2,577)				(5,812)
Interest income					107				107
Net loss					(2,470)				(5,705)
HighPeak II [Member] | Discontinued Operations, Disposed of by Means Other than Sale, Abandonment [Member]
Abandoned project					1,122				1,122
HighPeak II [Member] | Crude Oil Sales [Member]
Total operating revenues					513				719
HighPeak II [Member] | Natural Gas and NGL Sales [Member]
Total operating revenues					$ 42				$ 223