Stockholders' Equity And Stock-Based Compensation (Stock Repurchase) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Mar. 26, 2021	Dec. 25, 2020	Mar. 26, 2021	Mar. 27, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares repurchased (in shares)			1,207,418
Payments for Repurchase of Common Stock	$ 70,790	$ 39,985	$ 110,775	$ 101,672
Repurchase of common stock			$ 110,775
Stock Repurchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares repurchased (in shares)	757,019	450,399
Average Price Paid per Share (in dollars per share)	$ 93.51	$ 88.78	$ 93.51

Average Price Paid Per Share For Repurchase Activity

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- Definition

Payments For Repurchase Of Common Stock, Including Commissions

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- Definition

The cash outflow to reacquire common stock during the period.

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-Publisher FASB
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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