Consolidated Statements of Operations (USD $)
In Thousands, except Share data, unless otherwise specified
 12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Operating Costs and Expenses:    
General and administrative $ 5,832 $ 5,012
Research and development 6,507 12,287
Total Operating Costs and Expenses 12,339 17,299
Loss from Operations (12,339) (17,299)
Other Income (Expense):    
Interest income 33 33
Other expense (12) (18)
Total Other Income 21 15
Loss from Continuing Operations (12,318) (17,284)
Income from Discontinued Operations 0 216
Net Loss (12,318) (17,068)
Net Loss Attributable to Non-controlling Interest (1) 0
Net Loss Attributable to Synthetic Biologics, Inc. and Subsidiaries $ (12,317) $ (17,068)
Net Income (Loss) Per Share - Basic and Dilutive:    
Continuing operations (in dollars per share) $ (0.27) $ (0.50)
Discontinued operations (in dollars per share) $ 0 $ 0.01
Net Income (Loss) Per Share Attributable to Synthetic Biologics, Inc. and Subsidiaries (in dollars per share) $ (0.27) $ (0.49)
Weighted average number of shares outstanding during the period - Basic and Dilutive (in shares) 45,667,813 34,896,592