Liquidity and Going Concern (Details Narrative) - USD ($)	3 Months Ended
	Oct. 31, 2021	Oct. 31, 2020	Jul. 31, 2021
Liquidity And Going Concern
Cumulative net loss	$ 126,589,000		$ 125,793,000
Net loss	796,000	$ 180,000
Revenue	501,000	1,591,000
Net cash provided by (used) in operating and investing activities	630,000
Cash and cash equivalents	$ 1,760,000	$ 3,466,000	$ 2,390,000