Note 18 - Supplemental Crude Oil and Natural Gas Disclosures (Unaudited) - Standardized Measure of Discounted Future of Net Cash Flows (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020		Dec. 31, 2019	[1]
Future cash inflows	$ 3,668,535	$ 740,859
Future production costs	(824,865)	(217,025)
Future development costs	(432,370)	(117,887)
Future income tax expense	(431,737)	(25,824)
Future net cash flows	1,979,563	380,123
Discount to present value at 10% annual rate	(860,754)	(157,931)
Standardized measure of discounted future net cash flows	$ 1,118,809	$ 222,192	[1]	$ 140,032

[1] The year ended December 31, 2020 in the table above reflects the change in standardized measure from that of HPK LP, our Predecessor, as of December 31, 2019 to that of the Company as of December 31, 2020 and amounts are combined for the period from January 1, 2020 to August 21, 2020 of HPK LP and from August 22, 2020 to December 31, 2020 of the Company. There was no third-party reserve report prepared as of August 21, 2020 from which to compute a standardized measure from as of that date. We believe the table above accurately reflects the change in standardized measure for the Predecessor and Successor in a meaningful context.