| Document And Entity Information | Aug. 04, 2022 |
| Document Information [Line Items] | |
| Entity, Registrant Name | Alpha Pro Tech, Ltd. |
| Document, Type | 8-K |
| Document, Period End Date | Aug. 04, 2022 |
| Entity, Incorporation, State or Country Code | DE |
| Entity, File Number | 01-15725 |
| Entity, Tax Identification Number | 63-1009183 |
| Entity, Address, Address Line One | 60 Centurian Drive, Suite 112 |
| Entity, Address, City or Town | Markham |
| Entity, Address, State or Province | ON |
| Entity, Address, Country | CA |
| Entity, Address, Postal Zip Code | L3R 9R2 |
| City Area Code | 905 |
| Local Phone Number | 479-0654 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock |
| Trading Symbol | APT |
| Security Exchange Name | NYSE |
| Entity, Emerging Growth Company | false |
| Amendment Flag | false |
| Entity, Central Index Key | 0000884269 |
