Stockholders' Equity And Stock-Based Compensation (Stock Repurchase) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				12 Months Ended
	Sep. 27, 2019	Jun. 28, 2019	Mar. 29, 2019	Dec. 28, 2018	Sep. 27, 2019	Sep. 28, 2018	Sep. 29, 2017	Jul. 31, 2019	Jul. 25, 2018	Jan. 25, 2017	Oct. 31, 2014	Feb. 29, 2012	Jul. 31, 2011	Jul. 31, 2010	Nov. 30, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Repurchase Program, Authorized Amount	$ 2,000,000				$ 2,000,000										$ 250,000
Shares repurchased (in shares)	902,187	1,405,065	1,318,250	1,642,107	5,267,609
Cost	$ 54,011	$ 88,653	$ 85,351	$ 112,570	$ 340,585	$ 150,470	$ 100,000
Average Price Paid per Share (in dollars per share)	$ 59.94	$ 63.08	$ 64.73	$ 68.54	$ 59.94
Additional Stock Approved [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Repurchase Program, Authorized Amount								$ 350,000	$ 350,000	$ 200,000	$ 200,000	$ 100,000	$ 250,000	$ 300,000