Stockholders' Equity And Stock-Based Compensation (Stock Repurchase) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Jun. 26, 2020	Mar. 27, 2020	Dec. 27, 2019	Jun. 26, 2020	Jun. 28, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares repurchased (in shares)				1,921,863
Payments for Repurchase of Common Stock	$ 27,081	$ 71,669	$ 30,003	$ 128,753	$ 286,512
Repurchase of common stock				$ 128,753
Stock Repurchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares repurchased (in shares)	474,340	1,015,481	432,042
Average Price Paid per Share (in dollars per share)	$ 57.09	$ 70.57	$ 69.44	$ 57.09

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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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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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