Note 12 - Asset Retirement Obligations (Details Textual) - U1A Acquisition [Member] $ in Thousands	12 Months Ended
	Jul. 31, 2022 USD ($)
Asset Retirement Obligation, Obligation Assumed From Acquisition	$ 12,707
Minimum [Member]
Cash Flow Timing of Remediation and Decommissioning Activities (Year)	1 year
Maximum [Member]
Cash Flow Timing of Remediation and Decommissioning Activities (Year)	23 years