Percentage of compensation withheld by employees to purchase common stock.

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Percentage Of Target Award

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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, Estimated Forfeiture Rate

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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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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 210
-Name Accounting Standards Codification
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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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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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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

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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- Definition

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

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

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

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition

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

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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Percentage of vesting of award under share-based payment arrangement.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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) - USD ($)					1 Months Ended		12 Months Ended			41 Months Ended
	Dec. 15, 2023	Dec. 15, 2022	Dec. 15, 2021	Dec. 15, 2018	Dec. 31, 2023	Dec. 31, 2022	Sep. 27, 2024	Sep. 29, 2023	Sep. 30, 2022	Mar. 28, 2014	Aug. 31, 2024	Aug. 31, 2022	Feb. 28, 2022	Jul. 29, 2021	Dec. 15, 2020	Dec. 16, 2019	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								3,720,000
Estimated forfeiture rate, percent							8.53%	8.62%	8.63%
Tax benefit							$ 17,290,000	$ 17,844,000	$ 17,581,000
Stock authorized for repurchase							3,300,000,000																	$ 250,000,000
Remaining authorization to purchase additional shares							$ 401,600,000
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)							59,722,442	59,673,633
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)							35,670,779	36,085,779
2005 Stock Plan. [Member] \| Class A Common Stock [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Shares authorized under plan							64,000,000.0
Options vested and exercisable							2,780,000
Options outstanding to purchase							3,470,000
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]
Shares authorized under plan							5,500,000
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	$ 250,000,000	$ 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							$ 11,000,000.0
Employee stock options expected to be recognized over a weighted-average period							2 years 6 months
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							$ 195,500,000
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%
Employee Stock [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Tax benefit							$ 0	$ 0
Executive Officer [Member] \| Performance-Based Stock Options [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Percentage Of target award				75.00%
Grants in Period, Gross				241,100
Number of Exercisable Options				158,700
Options outstanding to purchase							226,110
Executive Officer [Member] \| Performance-Based Restricted Stock Units [Member]
Stockholders' Equity And Stock-Based Compensation [Line Items]
Percentage Of target award							200.00%
Grants in Period, Gross	77,283	90,613	60,301
Options outstanding to purchase							220,082								66,138	62,000
Executive Officer [Member] \| Performance Shares
Stockholders' Equity And Stock-Based Compensation [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage					80.00%	81.00%
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							440,164