Note 5 - Restricted Cash - Restricted Cash (Details) - USD ($)	12 Months Ended
	Jul. 31, 2020	Jul. 31, 2019
Restricted cash, beginning of period	$ 1,821,392	$ 1,789,899
Interest received	17,824	31,493
Restricted cash, end of period	$ 1,839,216	$ 1,821,392