Property and Equipment, Net - Schedule of Property and Equipment Net (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 839	$ 456
Less: Accumulated depreciation and amortization	(240)	(108)
Property and equipment, net	599	348
Laboratory Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	221	138
Furniture and Office Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	202	118
Computer Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	102	79
Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	44	44
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 270	$ 77