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Share-Based Employee Compensation (Summary of Performance Share Award Activity) (Details) - Deferred Compensation for Non Management Directors	12 Months Ended
	Sep. 27, 2020 $ / shares shares	Sep. 29, 2019 $ / shares shares	Sep. 30, 2018 shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Stock awards outstanding, Beginning balance, Shares | shares	100,005
Deferred directors’ compensation, Shares | shares	3,851
Dividend equivalents, Shares | shares	2,224
Stock distribution, Shares | shares	(204)	0	0
Stock awards outstanding, Ending balance, Shares | shares	105,876	100,005
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Stock awards outstanding, Weighted-Average Grant Date Fair Value, Beginning balance (in usd per share) | $ / shares	$ 38.87
Deferred directors' compensation, Weighted-Average Grant Date Fair Value (in usd per share) | $ / shares	81.56
Dividend equivalents, Weighted-Average Grant Date Fair Value (in usd per share) | $ / shares	$ 68.80
Dividend equivalents, Weighted- Average Grant Date Fair Value (in usd per share) | $ / shares	86.74
Stock awards outstanding, Weighted-Average Grant Date Fair Value, Ending balance (in usd per share) | $ / shares	$ 40.96	$ 38.87

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Deferred Directors' Compensation in Current Period, Shares

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Deferred directors' compensation, Weighted-Average Grant Date Fair Value

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Dividend Equivalents, Weighted Average Grant Date Fair Value, Per Share

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

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