Commitments and Contingencies - Future Minimum Lease Payments (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2019 Gross lease payment due	$ 1,777
2020 Gross lease payment due	1,788
2021 Gross lease payment due	1,839
2022 Gross lease payment due	1,894
2023 Gross lease payment due	1,951
Thereafter	7,296
Total Gross lease payment due	16,545
2019 Sublease income	(576)
2020 Sublease income	(148)
2021 Sublease income	0
2022 Sublease income	0
2023 Sublease income	0
Thereafter	0
Total Sublease income	(724)
2019 Net lease payment due	1,201
2020 Net lease payment due	1,640
2021 Net lease payment due	1,839
2022 Net lease payment due	1,894
2023 Net lease payment due	1,951
Thereafter	7,296
Total Net lease payment due	$ 15,821