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Percentage of compensation withheld by employees to purchase common stock.

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Percentage Of Target Award

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Percentage of vesting per year.

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Share based compensation arrangement by share based payment award maximum value of shares per employee.

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Share based compensation arrangement by share based payment award options becoming exercisable.

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Share-based Compensation Arrangement by Share-based Payment Award, Look Back Commencement Period

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Share-based Compensation Arrangement by Share-based Payment Award, Purchase Period

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Stockholders' Equity And Stock-Based Compensation [Line Items]

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Terms for issuance of stock.

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Year end stock price.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Minimum period the individual is required to perform services to be fully vested under the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Discount rate from fair value on purchase date that participants pay for shares.

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The highest quantity of shares an employee can purchase under the plan per period.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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Stockholders' Equity And Stock-Based Compensation (Narrative) (Details)							3 Months Ended		6 Months Ended		37 Months Ended	41 Months Ended
	Apr. 29, 2020 $ / shares	Jan. 29, 2020 $ / shares	Dec. 15, 2018 shares	Dec. 15, 2017 shares	Dec. 15, 2016 shares	Dec. 15, 2015 shares	Mar. 27, 2020 USD ($) vote $ / shares shares	Mar. 29, 2019 $ / shares	Mar. 27, 2020 USD ($) vote $ / shares shares	Mar. 29, 2019 $ / shares	Oct. 31, 2010	Mar. 28, 2014	Sep. 27, 2019 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													7,201,000
Year end stock price \| $ / shares									$ 53.94
Percentage of vesting per year											50.00%
Common stock, dividends declared (in dollars per share) \| $ / shares		$ 0.22					$ 0.22	$ 0.19	$ 0.44	$ 0.38
Remaining authorization to purchase additional shares \| $							$ 259,000,000		$ 259,000,000
Authorization Amount \| $							2,000,000,000		2,000,000,000												$ 250,000,000
Subsequent Event [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Common stock, dividends declared (in dollars per share) \| $ / shares	$ 0.22
Employee Stock Option [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Stock options expected to vest \| $							$ 29,900,000		$ 29,900,000
Employee stock options expected to be recognized over a weighted-average period									2 years 6 months
Performance-Based Stock Options [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Shares exercisable (in shares)							1,032,673		1,032,673
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									726,639
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)				330,000
Percentage Of Target Award				125.00%
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						334,623
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
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)							124,000		124,000
Percentage Of Target Award									200.00%
Options outstanding to purchase							62,000		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 \| $							$ 146,400,000		$ 146,400,000
Employee stock options expected to be recognized over a weighted-average period									2 years 9 months 18 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									2
Awards Granted Under 2005 Stock Plan From February 2011 [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Terms for issuance of stock									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	$ 200,000,000.0	$ 100,000,000	$ 250,000,000.0	$ 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)							64,422,131		64,422,131				63,911,270
Common stock, number of votes per share \| vote							1		1
Common stock, shares outstanding (shares)							64,422,131		64,422,131				63,911,270
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							7,059,000		7,059,000
Weighted average remaining contractual life									6 years 6 months 21 days
Options vested and exercisable							4,119,000		4,119,000
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									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)							36,224,820		36,224,820				36,229,820
Common stock, number of votes per share \| vote							10		10
Common stock, shares outstanding (shares)							36,224,820		36,224,820				36,229,820
Options Granted Prior To June 2008 [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 expiration period									10 years
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 expiration period									10 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]
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
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%
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%