Commitments and Contingencies - Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Operating Leases
Remaining 2020	$ 1,010
2021	1,536
2022	1,559
2023	1,594
2024	1,616
2025 and thereafter	7,617
Total	14,932
Amount representing interest	(2,488)
Amount representing leasehold incentives	(2,411)
Present value of future payments	10,033
Current portion of lease liability	(920)	$ (556)
Long-term portion of lease liability	9,113	9,389
Finance Leases
Remaining 2020	4
2021	0
2022	0
2023	0
2024	0
2025 and thereafter	0
Total	4
Amount representing interest	0
Amount representing leasehold incentives	0
Present value of future payments	4
Current portion of lease liability	(4)	$ (5)
Long-term portion of lease liability	$ 0