| Document And Entity Information | Dec. 02, 2022 |
| Document Information [Line Items] | |
| Entity, Registrant Name | FRIEDMAN INDUSTRIES, INCORPORATED |
| Document, Type | 8-K |
| Document, Period End Date | Dec. 02, 2022 |
| Entity, Incorporation, State or Country Code | TX |
| Entity, File Number | 1-07521 |
| Entity, Tax Identification Number | 74-1504405 |
| Entity, Address, Address Line One | 1121 Judson Road Suite 124 |
| Entity, Address, City or Town | Longview |
| Entity, Address, State or Province | TX |
| Entity, Address, Postal Zip Code | 75601 |
| City Area Code | 903 |
| Local Phone Number | 758-3431 |
| 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 | FRD |
| Security Exchange Name | NYSE |
| Entity, Emerging Growth Company | false |
| Amendment Flag | false |
| Entity, Central Index Key | 0000039092 |
