Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Future operating lease payments
2020 (remaining nine months)	$ 1,305
2021	1,763
2022	133
Total undiscounted lease payments	3,201
Less: Current portion of operating lease liabilities	(1,613)	$ (1,582)
Total operating lease liabilities, net of current portion	$ 1,426	$ 1,840