Document and Entity Information
| Document and Entity Information | Feb. 15, 2021 |
| Cover [Abstract] | |
| Entity Registrant Name | LAWSON PRODUCTS INC/NEW/DE/ |
| Amendment Flag | false |
| Entity Central Index Key | 0000703604 |
| Document Type | 8-K |
| Document Period End Date | Feb. 15, 2021 |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 0-10546 |
| Entity Tax Identification Number | 36-2229304 |
| Entity Address, Address Line One | 8770 W. Bryn Mawr Ave. |
| Entity Address, Address Line Two | Suite 900 |
| Entity Address, City or Town | Chicago |
| Entity Address, State or Province | IL |
| Entity Address, Postal Zip Code | 60631 |
| City Area Code | (773) |
| Local Phone Number | 304-5050 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common stock, $1.00 par value |
| Trading Symbol | LAWS |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |