Commitments and Contingencies - Future Undiscounted Cash Payments (Details) $ in Thousands	Sep. 30, 2019 USD ($)
Lessee, Lease, Description [Line Items]
Remaining 2019	$ 42
2020	23
Total	65
ROU Lease
Lessee, Lease, Description [Line Items]
Remaining 2019	22
2020	23
Total	45
Effect of discounting	(2)
Total accrued lease liability	$ 43