Note 10 - Income Taxes - Income Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Oct. 03, 2020	Sep. 28, 2019	Sep. 29, 2018
Provision for income taxes at federal statutory rate	$ 5,076	$ 1,566	$ 10,444
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%	24.50%
State income taxes, net of federal tax benefit	$ 319	$ 297	$ 739
State income taxes, net of federal tax benefit, percentage	1.30%	4.00%	1.70%
Stock-based compensation	$ 128	$ 90	$ (634)
Stock-based compensation, percentage	0.50%	1.20%	(1.50%)
Net operating loss carryback - CARES Act	$ (223)	$ 0	$ 0
Net operating loss carryback - CARES Act, percentage	(0.90%)	0.00%	0.00%
Valuation allowance	$ (50)	$ 24	$ (18)
Valuation allowance, percentage	(0.20%)	0.30%	(0.00%)
Federal tax return true-up	$ 0	$ (142)	$ (147)
Federal tax return true-up, percentage	0.00%	(1.90%)	(0.30%)
Change in federal tax rate - Tax Cuts and Jobs Act	$ 0	$ 0	$ (3,307)
Change in federal tax rate - Tax Cuts and Jobs Act, percentage	0	0	(0.078)
Qualified production activities deduction	$ 0	$ 0	$ (832)
Qualified production activities deduction, percentage	0.00%	0.00%	(2.00%)
Other, net	$ (89)	$ 22	$ 119
Other, net, percentage	(0.30%)	0.30%	0.30%
Provision for income taxes	$ 5,161	$ 1,857	$ 6,364
Provision for income taxes, percentage	21.40%	24.90%	14.90%

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