v3.26.1
Stockholders' Equity - Schedule of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($)
$ in Thousands
 9 Months Ended
Jun. 30, 2026
Jun. 30, 2025
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Beginning balance $ 1,726,986 $ 1,767,847
Other comprehensive income (loss) before reclassifications (6,574) (6,511)
Amounts reclassified from accumulated other comprehensive income (loss) 47 54
Ending balance 1,510,129 1,673,019
Accumulated Other Comprehensive Income (Loss)    
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Beginning balance (22,213) (13,464)
Ending balance (28,740) (19,921)
Currency Translation Adjustments    
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Beginning balance (12,918) (34,170)
Other comprehensive income (loss) before reclassifications (9,869) 33,176
Amounts reclassified from accumulated other comprehensive income (loss) 0 0
Ending balance (22,787) (994)
Unrealized Gains (Losses) on Available- for-Sale Securities Net of Tax    
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Beginning balance 213 (263)
Other comprehensive income (loss) before reclassifications (1,558) 262
Amounts reclassified from accumulated other comprehensive income (loss) 72 0
Ending balance (1,273) (1)
Gains (Losses) on Derivative Net of Tax    
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Beginning balance (8,729) 21,468
Other comprehensive income (loss) before reclassifications 4,985 (39,744)
Amounts reclassified from accumulated other comprehensive income (loss) 0 0
Ending balance (3,744) (18,276)
Pension Liability Adjustments Net of Tax    
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Beginning balance (779) (499)
Other comprehensive income (loss) before reclassifications (132) (205)
Amounts reclassified from accumulated other comprehensive income (loss) (25) 54
Ending balance $ (936) $ (650)