v3.26.1
Fair Value Measurements - Schedule of Accumulated Other Comprehensive Loss (Details) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Increase (Decrease) in Shareholders' Equity        
Beginning balance $ 1,696,961 $ 1,667,474 $ 1,674,035 $ 1,842,815
Other comprehensive income before reclassifications     947  
Amounts reclassified from accumulated other comprehensive loss     (3,801)  
Other comprehensive (loss)/income 334 5,746 (2,854) 19,831
Ending balance 1,740,551 1,773,036 1,740,551 1,773,036
Foreign currency translation adjustments        
Increase (Decrease) in Shareholders' Equity        
Beginning balance     (20,706)  
Other comprehensive income before reclassifications     (2,276)  
Amounts reclassified from accumulated other comprehensive loss     0  
Other comprehensive (loss)/income     (2,276)  
Ending balance (22,982)   (22,982)  
Net unrealized gain on derivatives, net of tax        
Increase (Decrease) in Shareholders' Equity        
Beginning balance     2,839  
Other comprehensive income before reclassifications     3,223  
Amounts reclassified from accumulated other comprehensive loss     (3,801)  
Other comprehensive (loss)/income     (578)  
Ending balance 2,261   2,261  
Total        
Increase (Decrease) in Shareholders' Equity        
Beginning balance (21,055) (18,375) (17,867) (32,460)
Ending balance $ (20,721) $ (12,629) $ (20,721) $ (12,629)