| Document and Entity Information | Mar. 17, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Mar. 17, 2021 |
| Entity Registrant Name | SMTC CORP |
| Entity Central Index Key | 0001108320 |
| Entity Emerging Growth Company | false |
| Entity File Number | 000-31051 |
| Entity Incorporation State Country Code | DE |
| Entity Tax Identification Number | 98-0197680 |
| Entity Address, Address Line One | 7050 Woodbine Avenue |
| Entity Address, City or Town | Markham |
| Entity Address, State or Province | ON |
| Entity Address, Country | CA |
| Entity Address, Postal Zip Code | L3R 4G8 |
| City Area Code | (905) |
| Local Phone Number | 479-1810 |
| Written Communications | false |
| Soliciting Material | true |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock, par value $0.01 per share |
| Trading Symbol | SMTX |
| Security Exchange Name | NASDAQ |
