Note 7 - Reconciliation of Income Tax Computed at U.S. Federal Statutory Tax Rate to Provision (Benefit) for Income Taxes for Continuing Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Tax provision (credit) at U.S. 35% statutory rate	$ 2,801	$ 6,802	$ (10,822)
State income taxes, net of federal tax benefit	(152)	119	(1,089)
Settlements, adjustments and releases from statute expirations	(104)	(65)	(849)
Federal tax credits	(221)	(244)	(1,340)
Stock-based compensation on which no tax benefit provided	156	160	168
Change in valuation allowance	2,181	437	9,574
Foreign income taxed at different rates	(2,601)	(2,151)	1,513
Other, net	151	(405)	472
	$ 2,211	$ 4,653	$ (2,373)