Note 10 - Provision for Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Balance at beginning of year	$ 61	$ 61	$ 0
Increases related to prior year tax positions	0	0	0
Decreases related to prior year tax positions	0	0	0
Increases related to current year tax positions	0	0	61
Settlements	0	0	0
Closure of tax years	(41)	0	0
Balance at end of year	$ 20	$ 61	$ 61