Note 7 - Income Taxes (Details Textual) - USD ($)	3 Months Ended			6 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 30, 2017	Apr. 01, 2017	Mar. 31, 2018	Sep. 29, 2018	Sep. 30, 2017
Effective Income Tax Rate Reconciliation, Percent	1.90%		33.80%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent				21.00%		35.00%
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability		$ 3,700,000
Deferred Tax Liabilities, Net, Noncurrent	$ 5,833,000			$ 5,833,000		$ 8,103,000
Deferred Tax Assets, Operating Loss Carryforwards, State and Local	7,400,000			7,400,000
Deferred Tax Assets, Valuation Allowance	254,000			254,000		$ 251,000
State and Local Jurisdiction [Member]
Deferred Tax Assets, Tax Credit Carryforwards	$ 71,000			$ 71,000
State and Local Jurisdiction [Member] | Earliest Tax Year [Member]
Operating Loss Carryforwards Expiration Date 1				2018
Tax Credit Carryforward, Expiration Date 1				2019
State and Local Jurisdiction [Member] | Latest Tax Year [Member]
Operating Loss Carryforwards Expiration Date 1				2031
Tax Credit Carryforward, Expiration Date 1				2020
Scenario, Forecast [Member]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent					24.50%