Percentage of compensation withheld by employees to purchase common stock.

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- Definition

Percentage Of Target Award

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No definition available.

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- Definition

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

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No definition available.

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- Definition

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

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Estimated Forfeiture Rate

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No definition available.

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- Definition

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

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No definition available.

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- Definition

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

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- Definition

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

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- Definition

Terms for issuance of stock.

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No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

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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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
-Subparagraph (i)
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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 718
-SubTopic 10
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- Definition

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

+ References

No definition available.

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of stock repurchase plan authorized.

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No definition available.

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Amount remaining of a stock repurchase plan authorized.

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Stockholders' Equity And Stock-Based Compensation (Narrative) (Details) - USD ($)							12 Months Ended			41 Months Ended
	Dec. 15, 2020	Dec. 16, 2019	Dec. 15, 2018	Dec. 15, 2017	Dec. 15, 2016	Dec. 15, 2015	Sep. 24, 2021	Sep. 25, 2020	Sep. 27, 2019	Mar. 28, 2014	Jul. 29, 2021	Jul. 31, 2019	Jul. 25, 2018	Jan. 25, 2017	Oct. 31, 2014	Feb. 29, 2012	Jul. 31, 2011	Jul. 31, 2010	Nov. 30, 2009
Stockholders' Equity And Stock-Based Compensation [Line Items]
Options outstanding to purchase								6,599,000
Estimated forfeiture rate, percent							8.85%	9.74%	9.78%
Stock authorized for repurchase							$ 2,350,000,000												$ 250,000,000
Remaining authorization to purchase additional shares							$ 291,300,000
Class A Common Stock [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Common stock, shares authorized (shares)							500,000,000	500,000,000
Common stock, shares issued (shares)							64,986,316	64,167,725
Class B Common Stock [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Common stock, shares authorized (shares)							500,000,000	500,000,000
Common stock, shares issued (shares)							36,086,779	36,128,720
2005 Stock Plan. [Member] \| Class A Common Stock [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Shares authorized under plan							55,000,000
Options vested and exercisable							3,071,000
Options outstanding to purchase							4,577,000
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%
Employee Stock Purchase Plan [Member] \| Class A Common Stock [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
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Period							6 months
Share-based Compensation Arrangement by Share-based Payment Award, Look Back Commencement Period							1 year
Additional Stock Approved [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Stock authorized for repurchase											$ 350,000,000	$ 350,000,000	$ 350,000,000	$ 200,000,000	$ 200,000,000	$ 100,000,000	$ 250,000,000	$ 300,000,000
Employee Stock Option [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Stock options expected to vest							$ 17,300,000
Employee stock options expected to be recognized over a weighted-average period							2 years
Employee Stock Option [Member] \| Options Granted From June 2008 [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Options vesting period							4 years
Percentage of stock option becoming exercisable subjected to date of grant							25.00%
Performance-Based Stock Options [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Options vesting period							3 years
Performance-Based Stock Options [Member] \| Minimum [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Percentage Of target award							0.00%
Performance-Based Stock Options [Member] \| Maximum [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Percentage Of target award							125.00%
Restricted Stock Units [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Stock options expected to vest							$ 170,400,000
Employee stock options expected to be recognized over a weighted-average period							2 years 4 months 24 days
Performance-Based Restricted Stock Units [Member] \| Minimum [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Percentage Of target award							0.00%
Performance-Based Restricted Stock Units [Member] \| Maximum [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Percentage Of target award							200.00%
Executive Officer [Member] \| Performance-Based Stock Options [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Percentage Of target award			125.00%	96.00%	95.00%	125.00%	125.00%
Grants in Period, Gross			241,100	264,000	276,199	419,623
Number of Exercisable Options			301,375	253,440	240,539	334,623
Options outstanding to purchase							604,737
Executive Officer [Member] \| Performance-Based Restricted Stock Units [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Percentage Of target award	200.00%	200.00%					200.00%
Number of Exercisable Options	132,276	124,000					657,637
Options outstanding to purchase	66,138	62,000					116,281
Employee and Officer [Member] \| Restricted Stock Units [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Options vesting period							4 years
Awards Granted Prior to November 2010 [Member] \| Director [Member] \| Restricted Stock Units [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Options vesting period										1 year
Share-based Payment Arrangement, Tranche Two \| Employee Stock Option [Member] \| Options Granted From June 2008 [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Options vesting period							36 months
Vesting Shares At 200% Of The Target Award Amount \| Executive Officer [Member] \| Performance-Based Restricted Stock Units [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Options outstanding to purchase							232,562