5. Commitments and Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Operating Lease Cost
Operating lease expense	$ 204	$ 177
Short term lease expense	39	14
Variable lease expense	33	34
Total operating lease cost	276	225
Finance Lease Cost
Amortization of right-of-use-assets	55	0
Interest on lease liabilities	21	0
Total finance lease cost	$ 76	$ 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 variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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