Note 6 - Pension Plans - Benefit Obligations and Plan Assets (Details) - Pension Plan [Member] - USD ($) $ in Thousands	12 Months Ended
Sep. 29, 2019	Sep. 30, 2018	Sep. 24, 2017
Benefit obligation, beginning of year	$ 176,531	$ 191,645
Service cost	36	48	$ 84
Interest cost	6,563	5,754	5,394
Actuarial loss (gain)	20,687	(9,464)
Benefits paid	(11,448)	(11,452)
Benefit obligation, end of year	192,369	176,531	191,645
Fair value of plan assets, beginning of year:	151,255	149,762
Actual return on plan assets	8,705	10,576
Benefits paid	(11,448)	(11,452)
Administrative expenses paid	(2,163)	(2,571)
Employer contributions	650	4,940
Fair value of plan assets, end of year	146,999	151,255	$ 149,762
Funded status	$ (45,370)	$ (25,276)

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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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 administration expense of defined benefit plan which decreases plan assets. Excludes plan administration expense paid by employer.

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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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