Leases - Future Minimum Lease Payments (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2020 Gross lease payment due	$ 1,777
2021 Gross lease payment due	1,788
2022 Gross lease payment due	1,839
2023 Gross lease payment due	1,894
2024 Gross lease payment due	1,951
Thereafter	7,296
Total Gross lease payment due	16,545
2020 Sublease income	(576)
2021 Sublease income	(148)
2022 Sublease income	0
2023 Sublease income	0
2024 Sublease income	0
Thereafter	0
Total Sublease income	(724)
2020 Net lease payment due	1,201
2021 Net lease payment due	1,640
2022 Net lease payment due	1,839
2023 Net lease payment due	1,894
2024 Net lease payment due	1,951
Thereafter	7,296
Total Net lease payment due	$ 15,821

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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