Number of performance obligations for revenue recognized.

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Amount of asset related to consideration paid in advance for research and development expenses that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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Summary Of Significant Accounting Policies [Line Items]

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- Definition

Face amount or stated value per share of common stock.

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- Definition

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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- Definition

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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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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- Definition

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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- Definition

Amount of unrecognized tax benefits.

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Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Summary of Significant Accounting Policies - Additional Information (Detail) $ / shares in Units, $ in Thousands		3 Months Ended	9 Months Ended		12 Months Ended
	Dec. 19, 2024	Sep. 30, 2023	Sep. 30, 2024 USD ($) $ / shares	Sep. 30, 2023	Dec. 31, 2023 USD ($) item segment $ / shares	Dec. 31, 2022 USD ($) $ / shares	Dec. 31, 2021 USD ($)
Basis of Presentation [Line Items]
Common stock, par value \| $ / shares			$ 0.001		$ 0.001	$ 0.001
Prepaid R&D expense			$ 1,650		$ 7,245	$ 15,188
Expected life of options (in years)		6 years 3 months	6 years 3 months	6 years 3 months
Expected dividend yield		0.00%	0.00%	0.00%	0.00%	0.00%	0.00%
Unrecognized tax provisions					$ 0	$ 0
Unrecognized tax benefits, related interest and penalties					$ 0	$ 0
Number of operating segments \| segment					1
Subsequent Event [Member]
Basis of Presentation [Line Items]
Reverse stock split	0.083
CSL Vifor and CKDP Agreements [Member] \| License and milestone fees [Member]
Basis of Presentation [Line Items]
Number of performance obligations for revenue recognized \| item					1
Prior to Regulatory Approval [Member]
Basis of Presentation [Line Items]
Cost of goods sold							$ 0
Stock Options
Basis of Presentation [Line Items]
Expected life of options (in years)					6 years 3 months	6 years 3 months	6 years 3 months
Expected dividend yield					0.00%	0.00%	0.00%