License Agreements and Grants - National Institute of Health Grant (Details) - National Institute of Health Grant - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended		53 Months Ended
	Feb. 28, 2015	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and Development Arrangement, Contract to Perform for Others, Proposed Period	5 years
Total grant funding	$ 5,000	$ 100	$ 38	$ 200	$ 100
Cumulative amount awarded						$ 1,300