License fees incurred.

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- Definition

Percentage of eligible discount on the issue of instruments.

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No definition available.

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Proceeds from financial instrument subject to mandatory redemption.

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No definition available.

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Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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-Topic 852
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Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

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-Topic 820
-SubTopic 10
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- Definition

Amount of issuances of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are due within one year or operating cycle, if longer, from the balance sheet date.

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- Definition

Amount of cash inflow (outflow) from long-term debt by a related party. Related parties, include, but are not limited to, affiliates, owners or officers and their immediate families, and pension trusts.

+ References

No definition available.

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- Definition

A fee charged for services from professionals such as doctors, lawyers and accountants. The term is often expanded to include other professions, for example, pharmacists charging to maintain a medicinal profile of a client or customer.

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-Topic 946
-SubTopic 830
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- Definition

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

Amount of sublease income excluding finance and operating lease expense.

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-Topic 842
-SubTopic 20
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-Section 55
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- Definition

The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders. Securities issued include securities outstanding and securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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Related Party Transactions - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended			12 Months Ended
	Dec. 31, 2023	Oct. 31, 2023	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Oct. 01, 2023	Sep. 07, 2022
Related Party Transaction [Line Items]
Accounts payable current	$ 409		$ 2,563	$ 409		$ 409	$ 574
Sublease income						0	253
Proceeds from (repayments of) related party debt						$ 0	$ 0
Temporary equity, shares issued	6,825,483		6,825,483	6,825,483		6,825,483	6,825,483
Series A-1 Preferred Stock [Member]
Related Party Transaction [Line Items]
Temporary equity, shares issued	4,118,120		4,118,120	4,118,120		4,118,120	4,118,120
Series A-1 Preferred Stock [Member] \| Convertible preferred stock [Member]
Related Party Transaction [Line Items]
Temporary equity, shares issued									2,446,372
Series A-2 Preferred Stock [Member]
Related Party Transaction [Line Items]
Temporary equity, shares issued	1,649,188		1,649,188	1,649,188		1,649,188	1,649,188
Series A-2 Preferred Stock [Member] \| Convertible preferred stock [Member]
Related Party Transaction [Line Items]
Temporary equity, shares issued									437,282
Related Party [Member] \| Series A-1 Preferred Stock [Member] \| Convertible preferred stock [Member]
Related Party Transaction [Line Items]
Temporary equity, shares issued									2,237,846
Related Party [Member] \| Series A-2 Preferred Stock [Member] \| Convertible preferred stock [Member]
Related Party Transaction [Line Items]
Temporary equity, shares issued									437,282
Member of the Scientific Advisory Board [Member] \| Advisory Services Agreement [Member]
Related Party Transaction [Line Items]
Other payables current	$ 0		$ 0	$ 0	$ 0	$ 0	$ 0
Member of the Scientific Advisory Board [Member] \| Advisory Services Agreement [Member] \| Maximum [Member]
Related Party Transaction [Line Items]
Professional fees			100		100	100	100
Harvard College [Member] \| License Agreement [Member]
Related Party Transaction [Line Items]
License fees incurred			100		100	200	100
Harvard College [Member] \| License Agreement [Member] \| Maximum [Member]
Related Party Transaction [Line Items]
Accounts payable current	100		100	100	$ 100	100	$ 0
Related Party Investors [Member] \| Simple Agreement For Future Equity [Member]
Related Party Transaction [Line Items]
Proceeds from financial instrument subject to mandatory redemption				34,100
Percentage of eligible discount of the issue of instruments		10.00%						10.00%
Fair value measurement with unobservable inputs reconciliation recurring basis liability issues	21,400	$ 10,400		10,400
Fair value measurement with unobservable inputs reconciliation recurring basis liability gain loss included in earnings	2,600	$ 300
Fair value measurement with unobservable input recnciliation basis liability value	$ 30,500		$ 32,600	$ 30,500		$ 30,500