| Document And Entity Information | Oct. 31, 2024 |
| Document Information [Line Items] | |
| Entity, Registrant Name | Cohu, Inc. |
| Document, Type | 8-K |
| Document, Period End Date | Oct. 31, 2024 |
| Entity, Incorporation, State or Country Code | DE |
| Entity, File Number | 001-04298 |
| Entity, Tax Identification Number | 95-1934119 |
| Entity, Address, Address Line One | 12367 Crosthwaite Circle |
| Entity, Address, City or Town | Poway |
| Entity, Address, State or Province | CA |
| Entity, Address, Postal Zip Code | 92064 |
| City Area Code | 858 |
| Local Phone Number | 848-8100 |
| Title of 12(b) Security | Common Stock |
| Trading Symbol | COHU |
| Security Exchange Name | NASDAQ |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity, Emerging Growth Company | false |
| Amendment Flag | false |
| Entity, Central Index Key | 0000021535 |
