Annual report pursuant to Section 13 and 15(d)

Equity - Narrative (Details)

v3.23.3
Equity - Narrative (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
 12 Months Ended
Sep. 30, 2023
Sep. 30, 2022
Sep. 30, 2021
Mar. 31, 2020
Stock-based compensation        
Deferred vested award (in shares) 286      
Intrinsic value vested $ 48,700      
Share-based compensation expense 29,500 $ 30,500 $ 28,600  
Income tax benefit recognized 8,100 $ 6,900 $ 13,500  
Unrecognized compensation cost $ 42,100      
Unrecognized compensation costs, period for recognition 4 years      
Granted (in dollars per share) $ 70.38      
Stock repurchase programs, authorized amount       $ 200,000
Common shares repurchased (in shares)   1,400 100  
Common shares repurchased, cost $ 0 $ 96,119 $ 3,363  
Amount remaining available for future stock repurchases 50,600      
Restricted Stock Units        
Stock-based compensation        
Granted (in dollars per share)   $ 79.75 $ 76.80  
Total fair value $ 29,800 $ 23,500 $ 28,900  
Restricted Stock Units | Member of Board of Directors        
Stock-based compensation        
Vesting period 1 year      
Restricted Stock Units | Minimum        
Stock-based compensation        
Vesting period 3 years      
Restricted Stock Units | Maximum        
Stock-based compensation        
Vesting period 5 years      
Performance Stock Units        
Stock-based compensation        
Vesting period 3 years      
Unrecognized compensation costs, period for recognition 3 years      
Performance Stock Units | Minimum        
Stock-based compensation        
Vesting rights, percentage 0.00%      
Performance Stock Units | Maximum        
Stock-based compensation        
Vesting rights, percentage 200.00%