Fair Value of Financial Instruments - Summary of Financial Instruments Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Liabilities
Essentialis purchase price contingency liability	$ 14,791	$ 11,549
Fair Value, Measurements, Recurring [Member]
Assets
Total cash equivalents	59,885
Total marketable securities	230,720
Total assets	290,605	157,281
Liabilities
Essentialis purchase price contingency liability	14,791	11,549
Total liabilities	14,791	11,549
Fair Value, Measurements, Recurring [Member] \| Money Market Funds [Member]
Assets
Total cash equivalents	59,885	157,281
Fair Value, Measurements, Recurring [Member] \| US Treasury Securities [Member]
Assets
Total marketable securities	198,065
Fair Value, Measurements, Recurring [Member] \| Corporate Debt Securities and Commercial Paper [Member]
Assets
Total marketable securities	32,655
Level 1 [Member] \| Fair Value, Measurements, Recurring [Member]
Assets
Total cash equivalents	59,885
Total assets	59,885	157,281
Level 1 [Member] \| Fair Value, Measurements, Recurring [Member] \| Money Market Funds [Member]
Assets
Total cash equivalents	59,885	157,281
Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Assets
Total marketable securities	230,720
Total assets	230,720
Level 2 [Member] \| Fair Value, Measurements, Recurring [Member] \| US Treasury Securities [Member]
Assets
Total marketable securities	198,065
Level 2 [Member] \| Fair Value, Measurements, Recurring [Member] \| Corporate Debt Securities and Commercial Paper [Member]
Assets
Total marketable securities	32,655
Level 3 [Member] \| Fair Value, Measurements, Recurring [Member]
Liabilities
Essentialis purchase price contingency liability	14,791	11,549
Total liabilities	$ 14,791	$ 11,549

Amount of liability recognized from contingent consideration in asset acquisition, classified as noncurrent.

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Fair value portion of asset recognized for present right to economic benefit.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value of financial and nonfinancial obligations.

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