Commitments and Contingencies - Leases, Components of lease expense (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($)
Commitments and Contingencies
Operating lease cost	$ 223
Variable lease cost	139
Total lease cost	$ 362
Weighted-average remaining operating lease term (years)	2 years 4 months 24 days
Weighted-average discount rate	8.56%

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- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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