Fair Value of Financial Assets and Liabilities - Schedule of Convertible Note Valuation Model (Details) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021 USD ($) $ / shares	Dec. 31, 2020 USD ($) $ / shares
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Face value | $	$ 4,000	$ 4,000
Coupon rate		12.00%
Stock price | $ / shares	$ 0.12	$ 0.19
Term		7 months 6 days
Risk-Free Interest Rate
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Valuation input for convertible note		0.09
Volatility
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Valuation input for convertible note		70
Minimum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Coupon rate	12.00%
Term	1 year
Minimum | Risk-Free Interest Rate
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Valuation input for convertible note	0.07
Maximum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Coupon rate	17.00%
Term	2 years
Maximum | Risk-Free Interest Rate
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Valuation input for convertible note	0.25