Note 12 - Discontinued Operations - Summary of Operating Results (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Income (loss), net of tax	$ 119	$ (278)	$ (221)
Broadcast Microwave Services, Inc. (“BMS”) [Member]
Net sales	1,593
Operating income	157
Loss from sale of BMS		(278)	(221)
Income (loss) before taxes	157	(278)	(221)
Income tax provision	38
Income (loss), net of tax	$ 119	$ (278)	$ (221)

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

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