Note L - Stock Options (Details Textual) - USD ($)	12 Months Ended
Sep. 29, 2018	Sep. 30, 2017	Sep. 24, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	624,000
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Offering Date	85.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 6,800,000	$ 10,100,000	$ 8,400,000
Proceeds from Stock Options Exercised	7,400,000	5,800,000	5,300,000
Employee Service Share-based Compensation, Tax Benefit from Exercise of Stock Options	$ 1,700,000	$ 3,000,000	$ 1,600,000
Incentive Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 23.68	$ 18.84	$ 13.94
Non-qualified Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 31.44	$ 24.82	$ 19.95
Employee Stock Purchase Plan [Member]
Stock Issued During Period, Shares, Employee Stock Purchase Plans	12,763	13,271	13,747
Share Price	$ 119.39	$ 105.85	$ 96
Allocated Share-based Compensation Expense, Total	$ 423,000	$ 363,000	$ 305,000

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Amount of tax benefit from exercise of stock options granted under share-based compensation arrangement.

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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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