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Stockholders' Equity - Stock Option Activity (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Jun. 09, 2022
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures
Authorized shares under the plan (in shares)			3,150,000		5,150,000
Share-based payment arrangement, plan modification, incremental cost	$ 600,000
Options to purchase Common Stock
Weighted-average assumptions
Risk-free interest rate		3.62%	1.87%
Dividend yield (as a percent)		0.00%	0.00%
Expected volatility (as a percent)		109.00%	106.00%
Expected term(1)		5 years 3 months 18 days	6 years
Number of Options
Balance outstanding at the beginning of the period (in shares)		5,069,458
Granted (in shares)		2,138,624
Forfeited and expired (in shares)		(555,655)
Balance outstanding at the end of the period (in shares)	6,652,427	6,652,427
Exercisable at the end of the period (in shares)	2,944,474	2,944,474
Vested and expected to vest (in shares)	6,459,779	6,459,779
Weighted Average Exercise Price Per Share
Balance outstanding at the beginning of the period (in USD per share)		$ 5.92
Granted (in USD per share)		1.70
Forfeited and expired (in USD per share)		8.40
Balance outstanding at the end of the period (in USD per share)	$ 4.36	4.36
Exercisable at the end of the period (in USD per share)	5.88	5.88
Vested and expected to vest (in USD per share)	$ 4.42	$ 4.42
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures
Options outstanding, intrinsic value	$ 18,747	$ 18,747		$ 19,322
Exercisable at the end of the period, intrinsic value	18,169	18,169
Vested and expected to vest, intrinsic value	$ 18,718	$ 18,718
Inducement Grant Stock Options
Number of Options
Granted (in shares)	1,435,256
Equity Incentive Plan 2021
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures
Number of remaining shares available for issuance (in shares)	2,013,871	2,013,871

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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