Closing prices of company common stock description.

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The percentage of net profits sharing.

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The amount of potential milestone payment of common stock investment.

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The amount of potential payment upon achievement of certain sales-based milestones.

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- Definition

The premium related to the common stock investment upon regulatory approval of CR845.

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Revenue performance obligation upfront payment received.

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The length of time used to set the price in the common stock investment upon regulatory approval of CR845.

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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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The cash inflow from the additional capital contribution to the entity.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Per share or per unit amount of equity securities issued.

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Number of new stock issued during the period.

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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Collaboration and Licensing Agreements - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands				1 Months Ended		3 Months Ended
	Aug. 23, 2021	Oct. 15, 2020	May 17, 2018	Oct. 31, 2021	Oct. 31, 2020	Mar. 31, 2022	Mar. 31, 2021
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue from contract with customer						$ 4,790	$ 1,935
Collaborative Revenue
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue from contract with customer							706
Commercial Supply Revenue
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue from contract with customer						4,790
Clinical Compound Revenue
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue from contract with customer							37
Vifor Agreement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of net profit sharing	60.00%				60.00%
Vifor Fresenius Medical Care Renal Pharma Ltd. [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Non-refundable, non-creditable upfront payment			$ 50,000
Common stock, shares issued			1,174,827
Purchase of common stock value			$ 20,000
Purchase common stock per share amount			$ 17.024
Closing prices of company common stock description			over a pre-determined average closing price of the Company’s common stock
Vifor Fresenius Medical Care Renal Pharma Ltd. [Member] \| Maximum [Member] \| Regulatory and Commercial Milestones [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential milestone payments			$ 455,000
Vifor Fresenius Medical Care Renal Pharma Ltd. [Member] \| Maximum [Member] \| Regulatory Milestones [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential milestone payments						15,000
Vifor Fresenius Medical Care Renal Pharma Ltd. [Member] \| Maximum [Member] \| Tiered Commercial Milestones [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential milestone payments						440,000
Maruishi Pharmaceutical Co., Ltd. [Member] \| Clinical Compound Revenue
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue from contract with customer						$ 0	$ 37
Vifor International Ltd. [Member] \| Vifor Agreement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of net profit sharing	40.00%				40.00%
Common stock, shares issued					2,939,552
Purchase common stock per share amount					$ 17.0094
Vifor International Ltd. [Member] \| Vifor Agreement [Member] \| License [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Non-refundable, non-creditable upfront payment					$ 100,000
Vifor International Ltd. [Member] \| Regulatory Milestones [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Common stock, shares issued				3,282,391
Proceeds from the sale of common stock		$ 50,000		$ 50,000
Purchase common stock per share amount				$ 15.23
Percentage of premium on common stock investment				20.00%
Stock issuance price measurement period				30 days
Vifor International Ltd. [Member] \| Maximum [Member] \| Sales-based Milestones
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential sales-based milestone payments				$ 240,000