Quarterly report pursuant to Section 13 or 15(d)

Commitments and Contingencies - License Agreements (Details)

v3.10.0.1
Commitments and Contingencies - License Agreements (Details) - USD ($)
$ in Millions
 1 Months Ended 9 Months Ended
Jan. 31, 2018
Sep. 30, 2016
May 31, 2016
Sep. 30, 2015
Apr. 30, 2013
Sep. 30, 2018
Sep. 30, 2017
Dec. 31, 2017
Feb. 28, 2013
Dana Farber                  
License Agreements                  
Payments due when the Company achieves certain milestones per the license agreement                 $ 3.4
Amount of future potential milestone payments accrued as of the end of the reporting period           $ 0.0   $ 0.0  
Whitehead                  
License Agreements                  
Payments due when the Company achieves certain milestones per the license agreement         $ 3.6        
Amount of future potential milestone payments accrued as of the end of the reporting period           0.0      
Amount paid for annual license maintenance fees and research services           0.5 $ 0.8    
Fee paid as a result of entry into the Collaboration Agreement with Incyte $ 0.2                
Accounts payable and accrued expenses           0.2      
Whitehead | Common Stock                  
License Agreements                  
Shares issued         171,674        
TMRC                  
License Agreements                  
Up-front license fee       $ 1.0          
Payment of up-front license fee     $ 0.5 0.5          
Payments per indication due upon the successful achievement of clinical and regulatory milestones       $ 13.0          
Payments made upon achievement of development milestone   $ 1.0              
Payments made under the supply management agreement           $ 0.0 $ 0.4