Note 6 - Income Taxes (Details Textual) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount			$ 368,000
Deferred Tax Assets, Valuation Allowance, Total	$ 10,000,000		10,000,000
Operating Loss Carryforwards, Total	35,500,000		35,500,000
Income Taxes Paid, Net, Total	0	$ 0	$ 0	$ 0
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions	$ 231,000
Effective Income Tax Rate Reconciliation, Percent, Total	0.00%		0.00%