5. Commitments and Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Operating Lease Cost
Operating lease expense	$ 201	$ 219	$ 561	$ 543
Short term lease expense	75	18	104	71
Variable lease expense	29	31	89	80
Sub lease income	0	(50)	0	(118)
Total operating lease cost	305	218	754	576
Finance lease cost
Amortization of right-of-use-assets	94	0	155	0
Interest on lease liabilities	26	0	44	0
Total finance lease cost	$ 120	$ 0	$ 199	$ 0

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Amount of interest expense on finance lease liability.

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Amount of amortization expense attributable to right-of-use asset from finance lease.

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Amount of lease cost recognized by lessee for lease contract.

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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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Amount of operating lease expense. Excludes sublease income.

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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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Amount of sublease income excluding finance and operating lease expense.

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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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