Consolidated Statements of Stockholder's Equity - USD ($) $ in Thousands	Total	Net Investment Hedging	Cash Flow Hedging	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss Net Investment Hedging	Accumulated Other Comprehensive Loss Cash Flow Hedging
Beginning balance at Sep. 30, 2018	$ 874,589			$ 1,180	$ 1,558,403	$ (599,409)	$ (85,585)
Beginning balance (in shares) at Sep. 30, 2018				117,981,000
Common stock issued for employee stock-based awards	0			$ 15	(15)
Common stock issued for employee stock-based awards (in shares)				1,479,000
Shares surrendered by employees to pay taxes related to stock-based awards	(44,191)			$ (5)	(44,186)	0	0
Shares surrendered by employees to pay taxes related to stock-based awards (in shares)				(501,000)
Common stock issued	(140)				(140)
Common stock issued for employee stock purchase plan	8,798			$ 1	8,797
Common stock issued for employee stock purchase plan (in shares)				122,000
Compensation expense from stock-based awards	71,608				71,608
Net income (loss)	(37,286)					(37,286)
Repurchases of common stock	(89,995)			$ (40)	(89,955)
Repurchases of common stock (in shares)				(3,970,000)
Unrealized loss on hedging instruments, net of tax		$ (1,982)	$ (385)					$ (1,982)	$ (385)
Foreign currency translation adjustment	(7,209)						(7,209)
Unrealized gain on available-for-sale securities, net of tax	477						477
Change in pension benefits, net of tax	1,672						1,672
Ending balance at Jun. 29, 2019	1,215,595			$ 1,151	1,504,512	(197,056)	(93,012)
Ending balance (in shares) at Jun. 29, 2019				115,111,000
Beginning balance at Mar. 30, 2019	1,247,708			$ 1,181	1,523,949	(182,298)	(95,124)
Beginning balance (in shares) at Mar. 30, 2019				118,098,000
Common stock issued for employee stock-based awards	0			$ 4	(4)
Common stock issued for employee stock-based awards (in shares)				371,000
Shares surrendered by employees to pay taxes related to stock-based awards	(9,700)			$ (1)	(9,699)	0	0
Shares surrendered by employees to pay taxes related to stock-based awards (in shares)				(113,000)
Compensation expense from stock-based awards	15,234				15,234
Net income (loss)	(14,758)					(14,758)
Repurchases of common stock	(25,001)			$ (33)	(24,968)
Repurchases of common stock (in shares)				(3,245,000)
Unrealized loss on hedging instruments, net of tax	(2,644)						(2,644)
Foreign currency translation adjustment	4,393						4,393
Unrealized gain on available-for-sale securities, net of tax	175						175
Change in pension benefits, net of tax	188						188
Ending balance at Jun. 29, 2019	1,215,595			$ 1,151	1,504,512	(197,056)	(93,012)
Ending balance (in shares) at Jun. 29, 2019				115,111,000
Cumulative effect of new accounting principle in period of adoption | Accounting Standards Update 2016-16	72,261					72,261
Cumulative effect of new accounting principle in period of adoption | Accounting Standards Update 2014-09	367,378					367,378
Beginning balance at Sep. 30, 2019	$ 1,201,998			$ 1,149	1,502,949	(191,390)	(110,710)
Beginning balance (in shares) at Sep. 30, 2019	114,899,000			114,899,000
Common stock issued for employee stock-based awards	$ 0			$ 14	(14)
Common stock issued for employee stock-based awards (in shares)				1,370,000
Shares surrendered by employees to pay taxes related to stock-based awards	(33,232)			$ (4)	(33,228)	0	0
Shares surrendered by employees to pay taxes related to stock-based awards (in shares)				(449,000)
Common stock issued for employee stock purchase plan	8,980			$ 1	8,979
Common stock issued for employee stock purchase plan (in shares)				156,000
Compensation expense from stock-based awards	73,605				73,605
Net income (loss)	77,289					77,289
Unrealized loss on hedging instruments, net of tax		(3,790)						(3,790)
Foreign currency translation adjustment	2,677						2,677
Unrealized gain on available-for-sale securities, net of tax	278						278
Change in pension benefits, net of tax	1,334						1,334
Ending balance at Jun. 27, 2020	$ 1,327,567			$ 1,160	1,552,291	(115,673)	(110,211)
Ending balance (in shares) at Jun. 27, 2020	115,976,000			115,976,000
Beginning balance at Mar. 28, 2020	$ 1,274,081			$ 1,157	1,536,770	(150,351)	(113,495)
Beginning balance (in shares) at Mar. 28, 2020				115,695,000
Common stock issued for employee stock-based awards	0			$ 4	(4)
Common stock issued for employee stock-based awards (in shares)				412,000
Shares surrendered by employees to pay taxes related to stock-based awards	(9,661)			$ (1)	(9,660)	0	0
Shares surrendered by employees to pay taxes related to stock-based awards (in shares)				(131,000)
Compensation expense from stock-based awards	25,185				25,185
Net income (loss)	34,678					34,678
Unrealized loss on hedging instruments, net of tax		$ (1,148)						$ (1,148)
Foreign currency translation adjustment	3,089						3,089
Unrealized gain on available-for-sale securities, net of tax	822						822
Change in pension benefits, net of tax	521						521
Ending balance at Jun. 27, 2020	$ 1,327,567			$ 1,160	$ 1,552,291	(115,673)	$ (110,211)
Ending balance (in shares) at Jun. 27, 2020	115,976,000			115,976,000
Cumulative effect of new accounting principle in period of adoption | Accounting Standards Update 2016-02	$ (1,572)					$ (1,572)