Stock-based Compensation - Inducement Plan - Stock Option Activity (Details) - Inducement Plan - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2024	Dec. 31, 2023
OUTSTANDING OPTIONS
Outstanding at beginning of period	2,590,400
Options granted	130,000
Outstanding at end of period	2,720,400	2,590,400
WEIGHTED-AVERAGE EXERCISE PRICE
Outstanding at beginning of period	$ 1.97
Options granted	3.20
Outstanding at end of period	$ 2.03	$ 1.97
VESTED AND EXPECTED TO VEST
Outstanding options	2,136,200
Weighted-Average Exercise Price	$ 2.04
Weighted-Average Remaining Contractual Term	7 years 10 months 24 days
Aggregate Intrinsic Value (in thousands)	$ 2,184
ADDITIONAL DISCLOSURES
Outstanding options exercisable at end of period	1,060,375
Weighted-average exercise price exercisable at end of period	$ 1.98
Weighted-average contractual term outstanding	7 years 9 months 18 days	8 years
Weighted-average contractual term (years) exercisable	7 years 6 months
Aggregate intrinsic value (in thousands) outstanding at end of period	$ 2,784
Aggregate intrinsic value (in thousands) exercisable at end of period	$ 1,135

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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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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 exercisable or convertible options. 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 per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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