Document and Entity Information - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Feb. 18, 2020	Jun. 28, 2019
Document and Entity Information
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Entity Registrant Name	Synthetic Biologics, Inc.
Entity Central Index Key	0000894158
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Public Float			$ 8,950
Trading Symbol	SYN
Entity Common Stock, Shares Outstanding		16,956,865
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false