Organization - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Date of incorporation	Jun. 08, 2012
Accumulated deficit	$ 152,675	$ 134,855
Cash, cash equivalents and short and long-term investments	$ 259,300