XML 63 R52.htm IDEA: XBRL DOCUMENT v3.21.1
Stock Repurchases (Details Textual) - shares
9 Months Ended 235 Months Ended
Apr. 30, 2021
Apr. 30, 2021
Sep. 22, 2011
Number of stock options exercised 1,148,000    
Stock Repurchase Program 2011      
Stock Repurchase Program Additional Number Of Shares Authorized Approved     80,000,000
Stock Repurchased and Retired During Period, Shares   114,549,198  
Number of shares available for repurchase under stock repurchase program 81,450,802 81,450,802  
Common Stock | Stock Repurchase Program 2011      
Common stock authorized for repurchase (in shares)     196,000,000