Consolidated Statements of Cash Flows $ in Thousands	12 Months Ended
	Dec. 26, 2015 USD ($)	Dec. 27, 2014 USD ($)	Dec. 28, 2013 USD ($)
Broadcast Microwave Services, Inc. (“BMS”) [Member]
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Gain (loss) on disposal of segment	$ 3,573
Changes in current assets and liabilities, excluding effects from acquisitions and divestitures:
Proceeds from Divestiture of Businesses	$ 4,881
Cohu Electronics [Member]
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Gain (loss) on disposal of segment		$ (4,434)
Changes in current assets and liabilities, excluding effects from acquisitions and divestitures:
Proceeds from Divestiture of Businesses		10,258
Net income (loss)	$ 250	$ 8,708	$ (33,418)
Gain on sale of facility	(3,198)
Operating cash flows of discontinued operations	(1,039)	$ 9,466	$ 1,894
Depreciation and amortization	11,273	12,607	12,517
Share-based compensation expense	6,755	6,388	5,111
Accrued retiree benefits	2,185	787	662
Deferred income taxes	222	$ 832	$ (1,656)
Other assets	(326)
Loss on disposal and impairment of fixed assets	311
Other accrued liabilities	127
Accounts receivable	8,970	$ (18,656)	$ (1,585)
Inventories	(5,743)	(3,401)	11,656
Accrued compensation, warranty and other liabilities	(3,740)	6,218	(1,534)
Accounts payable	3,376	139	7,040
Deferred profit	(3,108)	2,181	3,448
Other current assets	2,420	(1,294)	(353)
Income taxes payable, including excess stock option exercise benefits	(828)	137	(365)
Net cash provided by operating activities	21,480	$ 19,678	$ 3,417
Net cash received from sale of facility	33,314
Purchases of property, plant and equipment	(6,586)	$ (1,457)	$ (3,607)
Purchases of short-term investments	(656)	(1,000)
Sales and maturities of short-term investments	$ 155	$ 1,045	$ 6,221
Payment for purchase of Ismeca, net of cash received			(53,463)
Other assets			(176)
Investing cash flows of discontinued operations	$ (74)	$ (209)	(301)
Net cash provided by (used in) investing activities	31,034	8,637	(51,326)
Cash flows from financing activities:
Cash dividends paid	(6,215)	(6,067)	(4,468)
Issuance of stock, net	1,233	1,891	1,316
Net cash used in financing activities	(4,982)	(4,176)	(3,152)
Effect of exchange rate changes on cash and cash equivalents	(3,047)	(4,922)	(79)
Net increase (decrease) in cash and cash equivalents	44,485	19,217	(51,140)
Cash and cash equivalents at beginning of year	70,885	51,668	102,808
Cash and cash equivalents at end of year	115,370	70,885	51,668
Supplemental disclosure of cash flow information:
Cash paid (refunded) during the year for income taxes	(253)	971	(900)
Inventory capitalized as capital assets	315	1,166	640
Dividends declared but not yet paid	1,573	$ 1,539	$ 1,504
Capitalized facility under build-to-suit lease	$ 682