Note 2 - Discontinued Operations (Details Textual) $ in Thousands	1 Months Ended		3 Months Ended		6 Months Ended
	Jun. 27, 2015 USD ($)	Jun. 28, 2014 USD ($)	Jun. 27, 2015 USD ($)	Jun. 28, 2014 USD ($)	Jun. 27, 2015 USD ($)	Jun. 28, 2014 USD ($)
Broadcast Microwave Services, Inc. (“BMS”) [Member] | Fair Value, Inputs, Level 3 [Member]
Disposal Group, Including Discontinued Operation, Contingent Consideration	$ 200		$ 200		$ 200
Broadcast Microwave Services, Inc. (“BMS”) [Member] | Divestiture-related Costs [Member]
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax			900		1,000
Broadcast Microwave Services, Inc. (“BMS”) [Member]
Disposal Group, Including Discontinued Operation, Consideration	8,000		8,000		8,000
Proceeds from Divestiture of Businesses	5,500				5,339
Disposal Group, Including Discontinued Operation, Contingent Consideration	$ 2,500		2,500		2,500
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax			$ 2,910		$ 3,010
Cohu Electronics [Member] | Divestiture-related Costs [Member]
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax				$ 700		$ 800
Cohu Electronics [Member]
Proceeds from Divestiture of Businesses		$ 9,500				9,886
Disposal Group, Including Discontinued Operation, Contingent Consideration		$ 500		500		500
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax				(4,248)		(4,133)
Broadcast Microwave Services, Inc. (“BMS”) and Cohu Electronics [Member]
Number of Non-core Business Segments Sold					2
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax			$ 3,959	$ (2,024)	$ 4,973	$ (1,427)