Note 11 - Related Party Transactions (Details Textual) shares in Millions, Pure in Millions, $ in Millions		1 Months Ended	6 Months Ended
	Jul. 31, 2023 shares	Apr. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	May 31, 2022
Existing Stockholders [Member] | Public Stock Offering [Member]
Stock Issued During Period, Shares, New Issues | shares	10
Pilot Exploration Inc. [Member]
Supply Commitment, Minimum Barrels of Produced Water				29.2
Pilot Exploration Inc. [Member] | Water Treatment Services [Member]
Related Party Transaction, Amounts of Transaction | $		$ 6.5	$ 1.5