Note 4 - Discontinued Operations (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 26, 2015	Dec. 27, 2014
Broadcast Microwave Services, Inc. (“BMS”) [Member]
Proceeds from Divestiture of Businesses		$ 4,881
Disposal Group, Including Discontinued Operation, Contingent Consideration		2,500
Contingent Consideration Receivable, Fair Value	300	500
Cohu Electronics [Member]
Proceeds from Divestiture of Businesses			10,258
Disposal Group, Including Discontinued Operation, Contingent Consideration			500
Initial Cash Proceeds from Divestiture of Businesses			$ 9,500