Annual report pursuant to Section 13 and 15(d)

Capital Stock Share Repurchases - Additional Information (Details)

v3.19.3
Capital Stock Share Repurchases - Additional Information (Details) - USD ($)
$ / shares in Units, $ in Millions
 12 Months Ended
Aug. 31, 2019
Aug. 31, 2018
Mar. 16, 2015
Oct. 01, 2014
Mar. 29, 2014
Sep. 28, 2011
Capital Unit [Line Items]            
Common stock, shares authorized 168,000,000 168,000,000        
Common stock, par value $ 0.20 $ 0.20        
Common stock, shares issued 81,920,679 81,423,584        
Cumulative Preferred Stock, shares authorized share 160,000          
Cumulative Preferred Stock, par value $ 1.00          
Cumulative Preferred Stock, issued 0          
Shares authorized in buyback program     7,000,000 7,000,000 7,000,000 7,000,000
Stock Repurchased During Period, Shares 1,016,134          
Stock Repurchased During Period, Value $ 22.5          
Treasury stock, shares 21,455,568 20,439,434        
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased 6,544,432          
Common Class A            
Capital Unit [Line Items]            
Common stock, shares authorized 168,000,000          
Common stock, par value $ 0.20          
Common stock, shares issued 81,920,679          
Common stock, shares outstanding 60,465,111          
Common Class B            
Capital Unit [Line Items]            
Common stock, shares authorized 1,500,000          
Common stock, par value $ 0.20          
Common stock, shares issued 0          
Common stock, shares outstanding   0