Notes Payable - Schedule of future payments under the 2021 Avenue Loan and under the 2022 MD Loan, net of unamortized debt discounts (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Notes Payable (Details) [Line Items]
Accrued and unpaid interest	$ 2	$ 0
Less unamortized debt issuance costs and original issue discounts	(1,196)	$ (1,654)
2021 Avenue Loan [Member]
Notes Payable (Details) [Line Items]
2022 (remainder)	0
2023	6,667
2024	13,333
2025	0
2026	0
2027	0
Thereafter	0
Subtotal of future principal payments	20,000
Accrued and unpaid interest	0
Less unamortized debt issuance costs and original issue discounts	(1,166)
Total	18,834
2022 MD Loan Member
Notes Payable (Details) [Line Items]
2022 (remainder)	0
2023	0
2024	0
2025	368
2026	326
2027	0
Thereafter	0
Subtotal of future principal payments	694
Accrued and unpaid interest	2
Less unamortized debt issuance costs and original issue discounts	(30)
Total	$ 666

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