Note 8 - 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. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
Interest cost	$ 86	$ 86	$ 258	$ 258
Service cost	70	84	209	254
Recognized net actuarial loss	38	44	114	130
Net periodic pension cost	$ 194	$ 214	$ 581	$ 642