Loans Payable - Schedule of Term Loans Payable (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Short-term Debt [Line Items]
Net notes payable, (all current)	$ 17,613	$ 0
Term Loan
Short-term Debt [Line Items]
Net notes payable, (all current)	25,000
Less: Unamortized debt discount and issuance costs	(8,887)
Promissory Notes
Short-term Debt [Line Items]
Net notes payable, (all current)	$ 1,500