Note 9 - Employee Benefit Plans - Net Periodic Pension Costs and Related Components (Details) - Supplemental Employee Retirement Plan [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 27, 2020	Jun. 29, 2019	Jun. 27, 2020	Jun. 29, 2019
Interest cost	$ 82	$ 96	$ 249	$ 288
Service cost	83	74	245	222
Recognized net actuarial loss	72	35	212	105
Net periodic pension cost	$ 237	$ 205	$ 706	$ 615