Stockholders' Equity And Stock-Based Compensation (Summary Of Stock Options Issued To Officers, Directors, And Employees Under 2000 Stock Incentive Plan And 2005 Stock Plan) (Details) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	Dec. 15, 2016	Dec. 15, 2015	Sep. 28, 2018	Sep. 28, 2012
Shares
Options outstanding at September 29, 2017			8,741,000
Grants			1,420,000
Exercises			(2,473,000)
Forfeitures and cancellations			(390,000)
Options vested and expected to vest at September 28, 2018			6,911,000
Weighted-Average Exercise Price
Options outstanding at September 29, 2017			$ 38.65
Grants			62.34
Exercises			37.33
Forfeitures and cancellations			40.58
Options outstanding at September 28, 2018			43.61
Options vested and expected to vest at September 28, 2018			43.06
Options exercisable at September 28, 2018			$ 37.88
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted Average Remaining Contractual Life, Options vested and expected to vest at September 28, 2012			6 years 6 months 21 days
Weighted Average Remaining Contractual Life, Options exercisable			5 years 8 months 13 days
Aggregate Intrinsic Value, Options outstanding			$ 192,397
Aggregate Intrinsic Value, Options vested and expected to vest			185,978
Aggregate Intrinsic Value, Options exercisable			$ 124,812
Year End Stock Price			$ 69.97
Two Thousand Five Stock Plan Member | Common Class A [Member]
Shares
Options outstanding at September 28, 2018			7,298,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted Average Remaining Contractual Life, Options outstanding			6 years 7 months 18 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number			3,889,000
Awards Granted Under 2005 Stock Plan Prior To February 2011 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Terms for issuance of stock			2
Awards Granted Under 2005 Stock Plan From February 2011 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Terms for issuance of stock			1.6
Employee Stock Option [Member] | Options Granted From June 2008 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Options maximum vesting period, months			4 years	36 months
Share Based Compensation Arrangement By Share Based Payment Award Options Becoming Exercisable			25.00%
Employee Stock Option [Member] | Options Granted Prior To June 2008 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Options expiration period			10 years
Performance-Based Stock Options [Member] | Awarded Fiscal 2017 [Member] | Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	276,199
Shares
Options outstanding at September 28, 2018			784,898
Performance-Based Stock Options [Member] | Awarded Fiscal 2016 [Member] | Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		335,699