Cover - shares	9 Months Ended
	Sep. 30, 2020	Oct. 15, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Cover [Abstract]
Entity Registrant Name	LAWSON PRODUCTS, INC.
Entity Central Index Key	0000703604
Document Type	10-Q
Document Period End Date	Sep. 30, 2020
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Current Reporting Status	Yes
Entity Emerging Growth Company	false
Entity Shell Company	false
Common Stock, Shares, Outstanding	9,025,617		9,007,411	8,996,267	9,043,771	8,956,981	8,983,162	8,962,450	8,955,930
Entity Address, Address Line One	8770 W. Bryn Mawr Avenue, Suite 900,
Entity Address, City or Town	Chicago,
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	0-10546
Entity Tax Identification Number	36-2229304
Entity Address, State or Province	IL
Entity Incorporation, State or Country Code	DE
City Area Code	(773)
Local Phone Number	304-5050
Title of 12(b) Security	Common stock, $1.00 par value
Trading Symbol	LAWS
Security Exchange Name	NASDAQ
Entity Interactive Data Current	Yes
Entity Common Stock, Shares Outstanding		9,030,327
Entity Address, Postal Zip Code	60631