Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Thousands								6 Months Ended
	Mar. 03, 2022	Feb. 09, 2022	Jan. 14, 2022	Mar. 18, 2021	Oct. 14, 2020	Nov. 26, 2019	Apr. 12, 2019	Jun. 30, 2022	Mar. 14, 2022	Dec. 31, 2021	Nov. 09, 2021	Mar. 23, 2021	Dec. 31, 2020	Nov. 29, 2019
Subsequent Event [Line Items]
Stock issued (in shares)				6,271,836		3,666,667	5,670,000
Class of warrant or right, outstanding (in shares)										13,257,160			13,354,403
Sale price (in dollars per share)						$ 12.00	$ 11.00
Class of Warrant or Right, Additional Exercise Price of Warrants or Rights											$ 0.01	$ 0.01		$ 0.001
Pre Funded Warrant
Subsequent Event [Line Items]
Convertible preferred stock exercise price (in dollars per share)						$ 11.999	$ 10.999
Class of warrant or right, outstanding (in shares)	766,666
Hercules Loan Agreement
Subsequent Event [Line Items]
Line Of Credit Facility, Terms, Additional Term Loan Advances Receivable, Tranche Two										$ 7,500
Line Of Credit Facility, Terms, Additional Term Loan Advances Receivable, Tranche Three										$ 10,000
Hercules Loan Agreement | Forecast
Subsequent Event [Line Items]
Debt Instrument, Debt Covenant, Minimum Cash Required								$ 33,000
Issuance on November 29, 2019
Subsequent Event [Line Items]
Convertible preferred stock exercise price (in dollars per share)										$ 3.65
Class of warrant or right, outstanding (in shares)										5,416,667
Equity Unit Purchase Agreements
Subsequent Event [Line Items]
Purchase agreement, term					36 months
Subsequent Event
Subsequent Event [Line Items]
Sale of Stock, Purchase Agreement, Shares Issued			230,414
Purchase Agreement, Shares Purchased			1,382,488
Accelerated Share Repurchases, Initial Price Paid Per Share			$ 2.17
Payments for Securities Purchased under Agreements to Resell			$ 3,000
Convertible preferred stock exercise price (in dollars per share)	$ 1.79
Stock issued (in shares)	900,000
Sale price (in dollars per share)	$ 1.80
Class of Warrant or Right, Additional Exercise Price of Warrants or Rights	$ 0.01
Proceeds from Issuance of Warrants	$ 3,000
Subsequent Event | Hercules Loan Agreement
Subsequent Event [Line Items]
Line Of Credit Facility, Terms, Additional Term Loan Advances Receivable, Tranche Three									$ 17,500
Debt Instrument, Debt Covenant, Minimum Cash Required		$ 30,000
Debt Instrument, Debt Covenant, Minimum Cash Required, Conditional Scenario		$ 20,000
Subsequent Event | Issuance on November 29, 2019
Subsequent Event [Line Items]
Convertible preferred stock exercise price (in dollars per share)			$ 2.17
Subsequent Event | Q1 2022 PIPE
Subsequent Event [Line Items]
Convertible preferred stock exercise price (in dollars per share)		$ 1.80
Aspire Capital Fund, LLC | Subsequent Event
Subsequent Event [Line Items]
Long-term Purchase Commitment, Amount			$ 50,000
Lincoln Park Capital Fund, LLC | Subsequent Event
Subsequent Event [Line Items]
Long-term Purchase Commitment, Amount			$ 50,000