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, 2021	$ 2,038,468	$ 1,172	$ 1,718,504	$ 414,656	$ (95,864)
Beginning balance (in shares) at Sep. 30, 2021		117,163,000
Common stock issued for employee stock-based awards		$ 18	(18)
Common stock issued for employee stock-based awards (in shares)		1,729,000
Shares surrendered by employees to pay taxes related to stock-based awards	(68,659)	$ (6)	(68,653)
Shares surrendered by employees to pay taxes related to stock-based awards (in shares)		(594,000)
Common stock issued for employee stock purchase plan	10,857	$ 1	10,856
Common stock issued for employee stock purchase plan (in shares)		110,000
Compensation expense from stock-based awards	133,283		133,283
Repurchases of common stock	(125,000)	$ (11)	(124,989)
Repurchases of common stock (in shares)		(1,046,000)
Net Income (Loss)	206,244			206,244
Gain (loss) on net investment hedges, net of tax	12,072				12,072
Foreign currency translation adjustment	(52,819)				(52,819)
Change in pension benefits, net of tax	2,724				2,724
Ending balance at Jun. 30, 2022	2,157,170	$ 1,174	1,668,983	620,900	(133,887)
Ending balance (in shares) at Jun. 30, 2022		117,362,000
Beginning balance at Mar. 31, 2022	2,083,977	$ 1,170	1,637,631	550,424	(105,248)
Beginning balance (in shares) at Mar. 31, 2022		116,976,000
Common stock issued for employee stock-based awards		$ 6	(6)
Common stock issued for employee stock-based awards (in shares)		558,000
Shares surrendered by employees to pay taxes related to stock-based awards	(18,064)	$ (2)	(18,062)
Shares surrendered by employees to pay taxes related to stock-based awards (in shares)		(172,000)
Compensation expense from stock-based awards	49,420		49,420
Net Income (Loss)	70,476			70,476
Gain (loss) on net investment hedges, net of tax	5,880				5,880
Foreign currency translation adjustment	(35,795)				(35,795)
Change in pension benefits, net of tax	1,276				1,276
Ending balance at Jun. 30, 2022	2,157,170	$ 1,174	1,668,983	620,900	(133,887)
Ending balance (in shares) at Jun. 30, 2022		117,362,000
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	117,472,000
Common stock issued for employee stock-based awards		$ 18	18
Common stock issued for employee stock-based awards (in shares)		1,766,000
Shares surrendered by employees to pay taxes related to stock-based awards	$ (81,194)	$ (7)	(81,187)
Shares surrendered by employees to pay taxes related to stock-based awards (in shares)		(609,000)
Common stock issued for employee stock purchase plan	10,592		10,592
Common stock issued for employee stock purchase plan (in shares)		102,000
Compensation expense from stock-based awards	117,475		117,475
Net Income (Loss)	199,937			199,937
Gain (loss) on net investment hedges, net of tax	14,005				14,005
Foreign currency translation adjustment	70,181				70,181
Change in pension benefits, net of tax	(356)				(356)
Ending balance at Jun. 30, 2023	$ 2,598,664	$ 1,186	1,767,442	927,674	(97,638)
Ending balance (in shares) at Jun. 30, 2023	118,731,000	118,731,000
Beginning balance at Mar. 31, 2023	$ 2,518,534	$ 1,182	1,749,574	866,276	(98,498)
Beginning balance (in shares) at Mar. 31, 2023		118,334,000
Common stock issued for employee stock-based awards		$ 6	6
Common stock issued for employee stock-based awards (in shares)		582,000
Shares surrendered by employees to pay taxes related to stock-based awards	(25,172)	$ (2)	(25,170)
Shares surrendered by employees to pay taxes related to stock-based awards (in shares)		(185,000)
Compensation expense from stock-based awards	43,044		43,044
Net Income (Loss)	61,398			61,398
Gain (loss) on net investment hedges, net of tax	521				521
Foreign currency translation adjustment	1,405				1,405
Change in pension benefits, net of tax	(24)				(24)
Ending balance at Jun. 30, 2023	$ 2,598,664	$ 1,186	$ 1,767,442	$ 927,674	$ (97,638)
Ending balance (in shares) at Jun. 30, 2023	118,731,000	118,731,000