Condensed Consolidated Statements of Stockholder's Equity Statement - USD ($) shares in Thousands, $ in Thousands		Total	Common Stock and Additional Paid in Capital	Treasury Stock	Accumulated Other Comprehensive Income	Accumulated Deficit	Number of Common Shares [Member]
Balance at Sep. 30, 2017			$ 6,185,088	$ (633,740)	$ 76,794	$ (3,980,458)
Common Stock, Shares, Issued at Sep. 30, 2017							101,672
Treasury Stock, Shares at Sep. 30, 2017				(30,008)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under stock plans, shares							1,028
Issuances under stock plans, Value			3,439
Stock-based compensation expense			18,944
Adjustments to Additional Paid in Capital, Other			0
Repurchases of Treasury Stock, shares				(4,107)
Repurchases of Treasury Stock, Value				$ 120,539
Other comprehensive income (loss)		$ 471			471
Cumulative effect of new accounting pronouncement	[1]					43,269
Net income (loss)		(130,278)				(130,278)
Common Stock, Shares, Issued at Mar. 31, 2018							102,700
Treasury Stock, Shares at Mar. 31, 2018				(34,115)
Balance at Mar. 31, 2018		1,462,990	6,207,471	$ (754,279)	77,265	(4,067,467)
Balance at Dec. 30, 2017			6,196,293	$ (679,225)	76,619	(4,092,099)
Common Stock, Shares, Issued at Dec. 30, 2017							102,565
Treasury Stock, Shares at Dec. 30, 2017				(31,331)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under stock plans, shares							135
Issuances under stock plans, Value			913
Stock-based compensation expense			10,265
Adjustments to Additional Paid in Capital, Other			0
Repurchases of Treasury Stock, shares				(2,784)
Repurchases of Treasury Stock, Value				$ 75,054
Other comprehensive income (loss)		646			646
Cumulative effect of new accounting pronouncement						0
Net income (loss)		24,632				24,632
Common Stock, Shares, Issued at Mar. 31, 2018							102,700
Treasury Stock, Shares at Mar. 31, 2018				(34,115)
Balance at Mar. 31, 2018		1,462,990	6,207,471	$ (754,279)	77,265	(4,067,467)
Balance at Sep. 29, 2018		1,472,844	6,222,988	$ (791,366)	73,944	(4,032,722)
Common Stock, Shares, Issued at Sep. 29, 2018							103,128
Treasury Stock, Shares at Sep. 29, 2018				(35,351)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under stock plans, shares							1,668
Issuances under stock plans, Value			9,339
Stock-based compensation expense			12,442
Adjustments to Additional Paid in Capital, Other			138
Repurchases of Treasury Stock, shares				(455)
Repurchases of Treasury Stock, Value				$ 12,148
Other comprehensive income (loss)		(8,863)			(8,863)
Cumulative effect of new accounting pronouncement	[2]					28,130
Net income (loss)		78,837				78,837
Common Stock, Shares, Issued at Mar. 30, 2019							104,796
Treasury Stock, Shares at Mar. 30, 2019				(35,806)
Balance at Mar. 30, 2019		1,580,719	6,244,907	$ (803,514)	65,081	(3,925,755)
Balance at Dec. 29, 2018			6,232,372	$ (803,208)	70,093	(3,966,640)
Common Stock, Shares, Issued at Dec. 29, 2018							104,156
Treasury Stock, Shares at Dec. 29, 2018				(35,800)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under stock plans, shares							640
Issuances under stock plans, Value			5,771
Stock-based compensation expense			6,626
Adjustments to Additional Paid in Capital, Other			138
Repurchases of Treasury Stock, shares				(6)
Repurchases of Treasury Stock, Value				$ 306
Other comprehensive income (loss)		(5,012)			(5,012)
Cumulative effect of new accounting pronouncement						0
Net income (loss)		40,885				40,885
Common Stock, Shares, Issued at Mar. 30, 2019							104,796
Treasury Stock, Shares at Mar. 30, 2019				(35,806)
Balance at Mar. 30, 2019		$ 1,580,719	$ 6,244,907	$ (803,514)	$ 65,081	$ (3,925,755)

[1] Due to the adoption of ASU 2016-09 "Improvements to Employee Share-Based Payment Accounting (Topic 718)".

[2] Due to the adoption of ASU 2014-09 "Revenue from Contracts with Customers (Topic 606)" using the modified retrospective approach.