Stockholder's Equity (Details Textuals 2) - USD ($)	12 Months Ended			68 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2020
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock authorized to purchase	10,000,000			10,000,000
Discount from market price	15.00%
Offering period	6 months
Maximum percentage of salary withheld for employee contribution	up to 10%
Compensation contribution limit in percentage	may not exceed 15
Number of shares of common stock issued pursuant to the ESPP	123,106	177,043	185,168	8,776,482
Shares were available for future grant under the Plan (in shares)	1,303,592			1,303,592
Maximum annual contributions per employee, percent		10.00%
Share-based compensation arrangement by share-based payment award, maximum employee contribution permitted value	$ 25,000			$ 25,000
Maximum annual contributions per employee, conditional percent		15.00%
2007 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock authorized to purchase	32,000,000			32,000,000
Shares were available for future grant under the Plan (in shares)	4,833,806			4,833,806