Note 11 - Discontinued Operations - Summary of Operating Results (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 30, 2017	Dec. 31, 2016	Dec. 26, 2015
Loss, net of tax	$ (278)	$ (221)	$ (5,542)
Broadcast Microwave Services, Inc. (“BMS”) [Member]
Net sales			6,965
Loss from operations			(1,963)
Loss from sale	(278)	(221)	(3,573)
Loss before taxes	(278)	(221)	(5,536)
Income tax provision			6
Loss, net of tax	$ (278)	$ (221)	$ (5,542)

Amount before tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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