Quarterly report pursuant to Section 13 or 15(d)

Nature of Business (Details)

v3.8.0.1
Nature of Business (Details) - USD ($)
$ / shares in Units, $ in Thousands
1 Months Ended 3 Months Ended 12 Months Ended
Jan. 08, 2018
Feb. 28, 2018
Jan. 31, 2018
Mar. 31, 2018
Mar. 31, 2017
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Stock Offering                
Net loss       $ 14,463 $ 11,515 $ 54,000 $ 47,700 $ 29,800
Accumulated deficit       169,729   155,266    
Total, Fair Value       $ 121,741   $ 72,049    
Over-allotment                
Stock Offering                
Shares issued   628,272            
Share price (in dollars per share)   $ 9.55            
Aggregate gross proceeds   $ 6,000            
Underwriting commissions and fees   $ 400            
Common Stock | IPO                
Stock Offering                
Shares issued   4,188,481            
Share price (in dollars per share)   $ 9.55            
Aggregate gross proceeds   $ 40,000            
Underwriting commissions and fees   $ 3,000            
Incyte | Stock Purchase Agreement                
Stock Offering                
Shares issued 793,021              
Share price (in dollars per share) $ 12.61              
Incyte | Common Stock | Private Placement                
Stock Offering                
Shares issued   144,505            
Aggregate gross proceeds   $ 1,400            
Incyte | Common Stock | Stock Purchase Agreement                
Stock Offering                
Shares issued     793,021          
Aggregate gross proceeds     $ 10,000