Commitments and Contingencies - Additional Information (Details) - Austin, Texas	9 Months Ended
	Sep. 30, 2017
Commitments and Contingencies [Line Items]
Operating lease agreement, commencement date	2015-01
Operating lease agreement, amended date	2016-09
Operating lease agreement, expiration date	Dec. 31, 2020
Laboratory Facility
Commitments and Contingencies [Line Items]
Operating lease agreement, commencement date	2017-02
Operating lease agreement, expiration date	Dec. 31, 2017