Note 2 - Discontinued Operations - Summary of Operating Results of Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 27, 2015	Jun. 28, 2014	Jun. 27, 2015	Jun. 28, 2014
Broadcast Microwave Services, Inc. (“BMS”) [Member]
Net sales	$ 2,344	$ 3,551	$ 6,965	$ 8,245
Operating loss before income taxes	(1,049)	$ (1,861)	(1,963)	$ (2,464)
Gain (loss) from disposal of segment	$ (2,910)		$ (3,010)
Cohu Electronics [Member]
Net sales		$ 1,907		$ 5,460
Operating loss before income taxes		(363)		(242)
Gain (loss) from disposal of segment		4,248		4,133
Net sales	$ 2,344	5,458	$ 6,965	13,705
Operating loss before income taxes	(1,049)	(2,224)	(1,963)	(2,706)
Gain (loss) from disposal of segment	$ (3,959)	2,024	(4,973)	1,427
Income tax provision		61	6	105
Income (loss), net of tax	$ (3,959)	$ 1,963	$ (4,979)	$ 1,322