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Weighted-average period over which cost not yet recognized is expected to be recognized for 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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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Number, after shares used to satisfy grantee's tax withholding obligation for award under share-based payment arrangement, of restricted shares issued. Excludes cash used to satisfy grantee's tax withholding obligation.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Number of shares issued under share-based payment arrangement.

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- Definition

Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Stock-Based Compensation - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value of common stock per share	$ 2.2		$ 2.2
Weighted-average grant-date fair value of options granted	$ 1.69	$ 2.91	$ 0.89	$ 3.14
Aggregate intrinsic value of stock options exercised	$ 0	$ 0	$ 0	$ 300,000
Gross unrecognized stock-based compensation expense	6,500,000		$ 6,500,000
Unrecognized stock-based compensation expense weighted average amortized period			2 years 4 months 24 days
Number of restricted stock units granted			24,260
Restricted Stock Units ('RSU')
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation expense weighted average amortized period			2 years
Gross unrecognized stock-based compensation expense	$ 2,200,000		$ 2,200,000
Issuance of restricted common units, net of tax withholdings, (Shares)			541,016
Restricted common units issued, gross			616,596
2022 Equity Inducement Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future issuance	49,618		49,618
2021 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future issuance	4,325,203		4,325,203
2019 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future issuance	263,628		263,628
2021 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future issuance	653,777		653,777
Number of shares issued	0	26,599	29,619	86,481
Apexigen Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future issuance	495,861		495,861