Note 10 - Commitments and Contingencies (Details Textual)	6 Months Ended
	Jun. 30, 2023 USD ($) T MMBbls bbl	Dec. 31, 2022 USD ($)	Jul. 01, 2022	Jun. 30, 2022 USD ($)
Operating Lease, Liability, Current	$ 622,000	$ 343,000
Operating Lease, Liability, Noncurrent	$ 269,000	0
TXU Energy Retail Company LLC [Member]
Letters of Credit Outstanding, Amount				$ 1,700,000
Crude Oil Delivery Commitments [Member]
Supply Commitment, Gross Barrels of Oil Delivered Per Day, Year One (Barrel of Oil) | bbl	5,000
Supply Commitment, Gross Barrels of Oil Delivered Per Day, Year Two (Barrel of Oil) | bbl	7,500
Supply Commitment, Gross Barrels of Oil Delivered Per Day, Remaining Term of Contract (Barrel of Oil) | bbl	10,000
Supply Commitment, Remaining Term of Contract (Year)	8 years
Number of Barrels, Delivered (Barrel of Oil) | bbl	25,239
Supply Commitment, Percent of Contracted Volume Delivered	48.00%
Supply Commitment, Remaining Minimum Amount Committed, Volume | MMBbls	17.7
Supply Commitment, Amount Committed	$ 14,200,000
Connection Fee Commitments [Member]
Supply Commitment, Amount Committed	553,000
Sand Commitments [Member]
Supply Commitment, Amount Committed	$ 19,100,000
Supply Commitment, Minimum Tons of Sand			1,700,000
Supply Commitment, Sand Purchased | T	762,000
Other Noncurrent Assets [Member]
Operating Lease, Right-of-Use Asset	$ 876,000	333,000
Other Liabilities [Member]
Operating Lease, Liability	891,000	$ 343,000
Other Current Liabilities [Member]
Operating Lease, Liability, Current	622,000
Other Noncurrent Liabilities [Member]
Operating Lease, Liability, Noncurrent	$ 269,000