Promissory Notes - Schedule of Promissory Notes (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Short-term Debt [Line Items]
Principal Amount	$ 417	$ 565
Carrying Amount	417	568
Long-term Note, less current portion	0	0
Vendor Note Payable
Short-term Debt [Line Items]
Principal Amount	75	105
Carrying Amount	$ 75	105
Vendor Note Payable \| Minimum
Short-term Debt [Line Items]
Interest Rate	0.25%
Vendor Note Payable \| Maximum
Short-term Debt [Line Items]
Interest Rate	4.00%
Small Business Association Paycheck Protection Program
Short-term Debt [Line Items]
Interest Rate	1.00%
Principal Amount	$ 342	460
Carrying Amount	$ 342	463
Promissory Note
Short-term Debt [Line Items]
Interest Rate
Principal Amount	$ 0	0
Carrying Amount	0	0
Convertible Note
Short-term Debt [Line Items]
Less: Current portion	$ (417)	$ (568)

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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