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Note 12 - Treasury Stock Transactions (Details Textual) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended	9 Months Ended
	Sep. 25, 2020	Jun. 02, 2020	Jun. 27, 2020	Sep. 26, 2020	Sep. 29, 2019	Sep. 28, 2019
Treasury Stock, Shares, Acquired (in shares)		1,858,139
Treasury Stock Acquired, Average Cost Per Share (in dollars per share)		$ 1.20
Treasury Stock, Value, Acquired, Cost Method		$ 2,200	$ 2,230
Repayments of Subordinated Debt, Total				$ 2,230
Stock Repurchase Program, 2016 [Member]
Treasury Stock, Shares, Acquired (in shares)					0
Note Issued to Acquire Treasury Stock [Member]
Notes Issued		$ 2,200
Debt Instrument, Interest Rate, Stated Percentage		9.00%
Repayments of Subordinated Debt, Total	$ 2,200
Debt Instrument, Maturity Date		Aug. 10, 2023