Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 28, 2020	Mar. 30, 2019
Cash flows from operating activities:
Net loss attributable to Cohu	$ (17,276)	$ (22,643)
Net loss attributable to noncontrolling interest		(44)
Adjustments to reconcile net loss to net cash provided by operating activities:
Gain on disposal of discontinued operation	(35)
Impairment charges related to indefinite lived intangibles	3,949
Loss on disposal of assets	88	378
Depreciation and amortization	12,956	15,044
Share-based compensation expense	3,611	3,693
Amortization of inventory step-up and inventory related charges	1,603	6,504
Deferred income taxes	(2,706)	(2,494)
Increase in accrued retiree medical benefits	254	192
Changes in other accrued liabilities	(106)	1,589
Changes in other assets	810	313
Interest capitalized associated with cloud computing implementation	(45)
Amortization of debt discounts and issuance costs	290
Changes in current assets and liabilities:
Customer advances	14,434	(600)
Accounts receivable	17,078	17,657
Inventories	(6,067)	2,475
Other current assets	(5,888)	(4,022)
Accounts payable	55	(3,480)
Deferred profit	1,619	1,374
Income taxes payable	7,454	(2,214)
Accrued compensation, warranty and other liabilities	(14,313)	(9,002)
Operating lease right-of-use assets	1,843
Current and long-term operating lease liabilities	(1,795)
Net cash provided by operating activities	17,813	4,720
Cash flows from investing activities:
Net cash received from sale of Fixtures Services business	2,975
Cash received from sale of fixed assets	74	5
Purchases of property, plant and equipment	(1,584)	(3,526)
Net cash provided by (used in) investing activities	1,465	(3,521)
Cash flows from financing activities:
Cash dividends paid	(2,483)	(2,443)
Issuance (repurchases) of common stock, net	253	(1,750)
Proceeds from construction loan	1,117
Repayments of long-term debt	(1,133)	(1,098)
Net cash used in financing activities	(2,246)	(5,291)
Effect of exchange rate changes on cash and cash equivalents	(1,488)	(488)
Net increase (decrease) in cash and cash equivalents	15,544	(4,580)
Cash and cash equivalents including discontinued operations at beginning of period	155,930	164,921
Cash and cash equivalents including discontinued operations at end of period	171,474	160,341
Cash held by discontinued operations at end of period (Note 10)		(820)
Cash and cash equivalents from continuing operations at end of period	171,474	159,521
Supplemental disclosure of cash flow information:
Cash paid for income taxes	690	3,797
Inventory capitalized as property, plant and equipment	238	116
Dividends declared but not yet paid	2,488	2,449
Property, plant and equipment purchases included in accounts payable	3,370	873
Cash paid for interest	7,308	5,130
ST Capitalized Cloud Computing [Member]
Supplemental disclosure of cash flow information:
Capitalized cloud computing service costs included in accounts payable	182	329
LT Capitalized Cloud Computing [Member]
Supplemental disclosure of cash flow information:
Capitalized cloud computing service costs included in accounts payable	$ 1,370	$ 1,515