Stockholders' Equity And Stock-Based Compensation (Narrative) (Details)										3 Months Ended		9 Months Ended		37 Months Ended	41 Months Ended
	Jul. 29, 2021 USD ($) $ / shares	May 04, 2021 $ / shares	Jan. 28, 2021 $ / shares	Dec. 15, 2020 shares	Dec. 16, 2019 shares	Dec. 15, 2018 shares	Dec. 15, 2017 shares	Dec. 15, 2016 shares	Dec. 15, 2015 shares	Jun. 25, 2021 USD ($) vote $ / shares shares	Jun. 26, 2020 $ / shares	Jun. 25, 2021 USD ($) vote $ / shares shares	Jun. 26, 2020 $ / shares	Oct. 31, 2010	Mar. 28, 2014	Sep. 25, 2020 shares	Jul. 31, 2019 USD ($)	Jul. 25, 2018 USD ($)	Jan. 25, 2017 USD ($)	Oct. 31, 2014 USD ($)	Feb. 29, 2012 USD ($)	Jul. 31, 2011 USD ($)	Jul. 31, 2010 USD ($)	Nov. 30, 2009 USD ($)
Stockholders' Equity And Stock-Based Compensation [Line Items]
Options outstanding to purchase																6,599,000
Year end stock price (in dollars per share) | $ / shares												$ 100.06
Percentage of vesting per year														50.00%
Tax benefit | $												$ 1,100,000
Cash dividend declared per common share (in dollars per share) | $ / shares		$ 0.22	$ 0.22							$ 0.22	$ 0.22	$ 0.66	$ 0.66
Remaining authorization to purchase additional shares | $										$ 37,400,000		$ 37,400,000
Authorization Amount | $										2,000,000,000		2,000,000,000												$ 250,000,000
Subsequent Event [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Cash dividend declared per common share (in dollars per share) | $ / shares	$ 0.22
Employee Stock Option [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Stock options expected to vest | $										$ 19,800,000		$ 19,800,000
Employee stock options expected to be recognized over a weighted-average period												2 years
Performance-Based Stock Options [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Shares exercisable (in shares)										815,962		815,962
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period												7 years
Compensation requisite measurement period												3 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures												755,687
Performance-Based Stock Options [Member] | Executive Officer [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Percentage Of Target Award												125.00%
Performance-Based Stock Options [Member] | Executive Officer [Member] | Awarded Fiscal 2018 [Member] [Domain]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Shares exercisable (in shares)							253,440
Percentage Of Target Award							96.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures							264,000
Performance-Based Stock Options [Member] | Executive Officer [Member] | Awarded Fiscal 2016 [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Percentage Of Target Award									125.00%
Options vested and exercisable (in shares)									334,623
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures									419,623
Performance-Based Stock Options [Member] | Executive Officer [Member] | Awarded Fiscal 2017 [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Shares exercisable (in shares)								240,539
Percentage Of Target Award								95.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures								276,199
Performance-Based Stock Options [Member] | Executive Officer [Member] | Awarded Fiscal 2019 [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Shares exercisable (in shares)						301,375
Percentage Of Target Award						125.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures						241,100
Performance-Based Restricted Stock Units [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Compensation requisite measurement period												3 years
Performance-Based Restricted Stock Units [Member] | Executive Officer [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Shares exercisable (in shares)				132,276	124,000
Percentage Of Target Award				200.00%	200.00%
Options outstanding to purchase				66,138	62,000
Restricted Stock Units (RSUs) [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period												4 years
Stock options expected to vest | $										$ 174,500,000		$ 174,500,000
Employee stock options expected to be recognized over a weighted-average period												2 years 7 months 6 days
Restricted Stock Units (RSUs) [Member] | Employees and Officers [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period												4 years
Restricted Stock Units (RSUs) [Member] | Awards Granted Prior to November 2010 [Member] | Directors [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period														3 years	1 year
Restricted Stock Units (RSUs) [Member] | Awards Granted After November 2010 [Member] | Directors [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period														2 years
Awards Granted Under 2005 Stock Plan Prior To February 2011 [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Terms for issuance of stock (in shares)												2
Awards Granted Under 2005 Stock Plan From February 2011 [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Terms for issuance of stock (in shares)												1.6
Employee Stock Purchase Plan [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Percentage of compensation withheld by employees to purchase common stock												10.00%
Common stock purchase price determined over percentage of closing price												15.00%
Additional Stock Approved [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Authorization Amount | $																	$ 350,000,000	$ 350,000,000	$ 200,000,000	$ 200,000,000	$ 100,000,000	$ 250,000,000	$ 300,000,000
Class A Common Stock [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Common stock, shares authorized (shares)										500,000,000		500,000,000				500,000,000
Common stock, shares issued (shares)										65,248,388		65,248,388				64,167,725
Common stock, number of votes per share | vote										1		1
Common stock, shares outstanding (shares)										65,248,388		65,248,388				64,167,725
Class A Common Stock [Member] | Subsequent Event [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Remaining authorization to purchase additional shares | $	$ 387,000,000
Class A Common Stock [Member] | 2005 Stock Plan. [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Shares authorized under plan										55,000,000.0		55,000,000.0
Options outstanding to purchase										5,292,000		5,292,000
Weighted average remaining contractual life												5 years 9 months 29 days
Options vested and exercisable (in shares)										3,553,000		3,553,000
Class A Common Stock [Member] | Employee Stock Purchase Plan [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Maximum value of common stock available for eligible employees | $												$ 25,000
Maximum number of common stock available for eligible employees (in shares)												1,000
Purchase period												6 months
Look back commencement period												1 year
Class B Common Stock [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Common stock, shares authorized (shares)										500,000,000		500,000,000				500,000,000
Common stock, shares issued (shares)										36,086,779		36,086,779				36,128,720
Common stock, number of votes per share | vote										10		10
Common stock, shares outstanding (shares)										36,086,779		36,086,779				36,128,720
Options Granted From June Two Thousand Eight Member | Employee Stock Option [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period												4 years
Options Granted From June Two Thousand Eight Member | Employee Stock Option [Member] | One year anniversary date
Stockholders' Equity And Stock-Based Compensation [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period												1 year
Percentage of stock option becoming exercisable subjected to date of grant												25.00%
Options Granted From June Two Thousand Eight Member | Employee Stock Option [Member] | Over 36 equally installment periods following one year anniversary date
Stockholders' Equity And Stock-Based Compensation [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period												36 months
Awards Granted Prior To November Two Thousand Ten Member [Member] | Restricted Stock Units (RSUs) [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period												3 years
Awards Granted After November 2010 and Prior To Fiscal 2014 Member [Member] | Restricted Stock Units (RSUs) [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period												2 years
Awards Granted After November 2010 Member [Member] | Restricted Stock Units (RSUs) [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period												1 year
Options Granted After June Two Thousand Eight Member [Member] | Employee Stock Option [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period												4 years
Minimum [Member] | Performance-Based Stock Options [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Percentage Of Target Award												0.00%
Minimum [Member] | Performance-Based Restricted Stock Units [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Percentage Of Target Award												0.00%
Minimum [Member] | Options Granted From June Two Thousand Eight Member | Employee Stock Option [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Options expiration period												3 months
Maximum [Member] | Performance-Based Stock Options [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Percentage Of Target Award												125.00%
Maximum [Member] | Performance-Based Restricted Stock Units [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Percentage Of Target Award												200.00%
Maximum [Member] | Options Granted From June Two Thousand Eight Member | Employee Stock Option [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Options expiration period												10 years