Consolidated Statements of Stockholder's Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Loss
Beginning balance at Sep. 30, 2022	$ 2,296,034	$ 1,175	$ 1,720,580	$ 727,737	$ (153,458)
Beginning balance (in shares) at Sep. 30, 2022		117,472,000
Common stock issued for employee stock-based awards		$ 11	(11)
Common stock issued for employee stock-based awards (in shares)		1,090,000
Shares surrendered by employees to pay taxes related to stock-based awards	(52,875)	$ (4)	(52,871)
Shares surrendered by employees to pay taxes related to stock-based awards (in shares)		(401,000)
Compensation expense from stock-based awards	34,119		34,119
Net Income (Loss)	75,035			75,035
Loss on net investment hedges, net of tax	(11,485)				(11,485)
Foreign currency translation adjustment	60,029				60,029
Change in defined benefit pension items, net of tax	(308)				(308)
Ending balance at Dec. 31, 2022	2,400,549	$ 1,182	1,701,817	802,772	(105,222)
Ending balance (in shares) at Dec. 31, 2022		118,161,000
Beginning balance at Sep. 30, 2023	$ 2,677,290	$ 1,188	1,820,905	973,277	(118,080)
Beginning balance (in shares) at Sep. 30, 2023	118,846,000	118,846,000
Common stock issued for employee stock-based awards		$ 10	(10)
Common stock issued for employee stock-based awards (in shares)		950,000
Shares surrendered by employees to pay taxes related to stock-based awards	$ (54,336)	$ (4)	(54,332)
Shares surrendered by employees to pay taxes related to stock-based awards (in shares)		(351,000)
Compensation expense from stock-based awards	94,371		94,371
Net Income (Loss)	66,387			66,387
Loss on net investment hedges, net of tax	(11,511)				(11,511)
Foreign currency translation adjustment	34,674				34,674
Change in defined benefit pension items, net of tax	(222)				(222)
Ending balance at Dec. 31, 2023	$ 2,806,653	$ 1,194	$ 1,860,934	$ 1,039,664	$ (95,139)
Ending balance (in shares) at Dec. 31, 2023	119,445,000	119,445,000