Note A - Summary of Significant Accounting Policies (Details Textual) $ in Thousands	12 Months Ended
Sep. 24, 2022 USD ($) shares	Sep. 25, 2021 USD ($) shares	Sep. 26, 2020 USD ($) shares
Contract with Customer, Asset, Allowance for Deductions	$ 14,700	$ 14,600
Accounts Receivable, Allowance for Credit Loss, Ending Balance	2,200	1,400
Cash, Uninsured Amount	13,000
Accounts Receivable, after Allowance for Credit Loss, Total	$ 208,200	162,900
Employees Covered Under Collective Bargaining Agreement, Percentage	26.00%
Unrecognized Tax Benefits, Ending Balance	$ 343	343
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total	$ 300	$ 300
Effective Income Tax Rate Reconciliation, Percent, Total	23.50%	24.90%	25.00%
Effective Income Tax Rate Reconciliation, State Deferred Taxes and Provision to Return Adjustment, Amount			$ 2,200
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares) \| shares	287,558	284,480	341,849
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate	25.80%	25.80%	17.40%
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	0.80%	0.80%	0.30%
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate	1.60%	1.40%	1.80%
Advertising Expense	$ 7,000	$ 4,900	$ 6,500
Unrecorded Unconditional Purchase Obligation, Total	130,000
Research and Development Expense, Total	$ 700	$ 600	$ 700
Five Year Options [Member]
Share Based Compensation Arrangement by Share Based Payment Award Fair Value Assumptions Volatility Calculation Term (Year)	51 years
Ten Year Options [Member]
Share Based Compensation Arrangement by Share Based Payment Award Fair Value Assumptions Volatility Calculation Term (Year)	10 years
Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period (in shares) \| shares	9,200	0	0
Performance Shares [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period (in shares) \| shares	8,868	0	0
Revenue Benchmark [Member] \| Customer Concentration Risk [Member]
Number of Major Customers	10	10	10
Minimum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	2 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term (Year)	4 years	4 years	4 years
Maximum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	20 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term (Year)	10 years	10 years	10 years
Customer Group One [Member]
Approximate Number of Customers	33
Customer Group One [Member] \| Minimum [Member]
Accounts Receivable, after Allowance for Credit Loss, Total	$ 1,000
Customer Group One [Member] \| Maximum [Member]
Accounts Receivable, after Allowance for Credit Loss, Total	10,000
Five Customers [Member] \| Minimum [Member]
Accounts Receivable, after Allowance for Credit Loss, Total	10,000
Largest Customer [Member]
Accounts Receivable, after Allowance for Credit Loss, Total	$ 23,000
Largest Customer [Member] \| Revenue Benchmark [Member] \| Customer Concentration Risk [Member]
Concentration Risk, Percentage	8.00%	11.00%	13.00%
Top Ten Customers [Member] \| Revenue Benchmark [Member] \| Customer Concentration Risk [Member]
Concentration Risk, Percentage	43.00%	43.00%	43.00%

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to state deferred taxes and provision to return adjustment.

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Represents the percentage of employees covered under a collective bargaining agreement.

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Represents the number of major customers accounting for 10% or more of the specified concentration risk benchmark, which includes, but not limited to, sales revenue, accounts receivable, etc.

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Number of shares issued under share-based payment arrangement.

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Expected term of 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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Amount of unrecognized tax benefits.

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