Note 7 - Pension Plans - Allocation of Benefit Plan Assets (Details) - Pension Plan [Member]	Sep. 27, 2020	Sep. 29, 2019
Defined Benefit Plan, Equity Securities [Member]
Asset Percentage, Policy Allocation	50.00%
Asset Percentage, Actual Allocation	48.00%	49.00%
Defined Benefit Plan, Debt Security [Member]
Asset Percentage, Policy Allocation	35.00%
Asset Percentage, Actual Allocation	33.00%	34.00%
US Treasury Securities [Member]
Asset Percentage, Policy Allocation	5.00%
Asset Percentage, Actual Allocation	5.00%	5.00%
Hedge Funds [Member]
Asset Percentage, Policy Allocation	10.00%
Asset Percentage, Actual Allocation	10.00%	10.00%
Defined Benefit Plan, Cash and Cash Equivalents [Member]
Asset Percentage, Policy Allocation	0.00%
Asset Percentage, Actual Allocation	4.00%	2.00%