Note 10 - Discontinued Operations - Assets and Liabilities of Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended
	Aug. 26, 2018	Aug. 27, 2017	May 27, 2018	May 28, 2017
Cash, discontinued operations		$ (73)	$ (8)	$ (589)
Loss from discontinued operations, before taxes		(203)
Income tax benefit		(60)
Loss from discontinued operations, net of tax		(143)
Discontinued Operations [Member] | Food Export [Member]
Cash, discontinued operations			(8)
Accounts receivable			518
Inventory
Other assets
Total assets, discontinued operations			510
Accounts payable			230
Accrued expenses and other current liabilities			228
Total other current liabilities, discontinued operations			$ 458
Revenues		7,576
Cost of sales		(7,092)
Selling, general and administrative		(687)
Other
Loss from discontinued operations, before taxes		(203)
Income tax benefit		60
Loss from discontinued operations, net of tax		$ (143)