Commitments and Contingencies - Operating Lease - Lease liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Future minimum lease payments at December 31, 2018
2019		$ 57
Total minimum payments		$ 57
Maturity of the lease liability was as follows (in thousands):
2020	$ 32
2021	32
Total lease payments	144
Head Quarters in Boston Lease [Member]
Maturity of the lease liability was as follows (in thousands):
2020	204
2021	21
Total lease payments	$ 225