Consolidated Statements of Stockholder's Equity - USD ($) $ in Thousands	Total	Net Investment Hedging	Common Stock	Additional Paid-In Capital	Retained Earnings (Accumulated Deficit)	Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss Net Investment Hedging
Beginning balance at Sep. 30, 2020	$ 1,438,248		$ 1,161	$ 1,602,728	$ (62,267)	$ (103,374)
Beginning balance (in shares) at Sep. 30, 2020			116,125,000
Common stock issued for employee stock-based awards			$ 15	(15)
Common stock issued for employee stock-based awards (in shares)			1,470,000
Shares surrendered by employees to pay taxes related to stock-based awards	(52,194)		$ (4)	(52,190)
Shares surrendered by employees to pay taxes related to stock-based awards (in shares)			459,000
Common stock issued for employee stock purchase plan	10,484		$ 1	10,483
Common stock issued for employee stock purchase plan (in shares)			144,000
Compensation expense from stock-based awards	$ 133,896			133,896
Repurchases of common stock (in shares)	0
Net income	$ 183,980				183,980
Unrealized loss on net investment hedges, net of tax		$ (1,559)					$ (1,559)
Foreign currency translation adjustment	10,581					10,581
Unrealized loss on marketable securities, net of tax	(307)					(307)
Change in pension benefits, net of tax	(1,829)
Ending balance at Jun. 30, 2021	1,724,958		$ 1,173	1,694,902	121,713	(92,830)
Ending balance (in shares) at Jun. 30, 2021			117,280,000
Beginning balance at Mar. 31, 2021	1,650,533		$ 1,169	1,676,791	70,510	(97,937)
Beginning balance (in shares) at Mar. 31, 2021			116,855,000
Common stock issued for employee stock-based awards			$ 6	(6)
Common stock issued for employee stock-based awards (in shares)			608,000
Shares surrendered by employees to pay taxes related to stock-based awards	(24,953)		$ (2)	(24,951)
Shares surrendered by employees to pay taxes related to stock-based awards (in shares)			(183,000)
Compensation expense from stock-based awards	$ 43,068			43,068
Repurchases of common stock (in shares)	0
Net income	$ 51,203				51,203
Unrealized loss on net investment hedges, net of tax		(1,797)					(1,797)
Foreign currency translation adjustment	6,457					6,457
Unrealized loss on marketable securities, net of tax	0
Change in pension benefits, net of tax	447					447
Ending balance at Jun. 30, 2021	1,724,958		$ 1,173	1,694,902	121,713	(92,830)
Ending balance (in shares) at Jun. 30, 2021			117,280,000
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		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)		(1,046,000)
Net income	$ 206,244				206,244
Unrealized loss on net investment hedges, net of tax		12,072					12,072
Foreign currency translation adjustment	(52,819)					(52,819)
Unrealized loss on marketable securities, net of tax	0
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		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
Repurchases of common stock (in shares)	0
Net income	$ 70,476				70,476
Unrealized loss on net investment hedges, net of tax		$ 5,880					$ 5,880
Foreign currency translation adjustment	(35,795)					(35,795)
Unrealized loss on marketable securities, net of tax	0
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		117,362,000