Note 11 - Employee Benefit Plans - Projected Benefit Obligation Reconciliation for SERP (Details) - Supplemental Employee Retirement Plan [Member] - USD ($) $ in Thousands	12 Months Ended
Sep. 28, 2019	Sep. 29, 2018	Sep. 30, 2017
Benefit obligation	$ 9,749	$ 9,389	$ 9,159
Service cost	297	310	344
Interest cost	384	345	338
Actuarial loss (gain)	1,133	(33)	(162)
Distributions	(285)	(262)	(290)
Benefit obligation	11,278	9,749	9,389
Actual employer contributions	285	262	290
Actual distributions	(285)	(262)	(290)
Fair value of plan assets
Funded status	(11,278)	(9,749)	(9,389)
Net amount recognized	(11,278)	(9,749)	(9,389)
Unrecognized net loss	2,958	1,966	2,149
Net amount recognized	2,958	1,966	2,149
Net loss (gain)	1,133	(33)	(162)
Amortization of net loss	(140)	(150)	(174)
Total recognized in other comprehensive income (loss)	$ 993	$ (183)	$ (336)

Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

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Amount, before tax, after reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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Amount, before tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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