Net Income (Loss) per Share - Additional Information (Detail) - USD ($) $ in Thousands	Oct. 15, 2020	Mar. 31, 2021	Mar. 31, 2020
Number of options outstanding		5,918,808	4,930,590
Number of restricted stock units outstanding		401,831	355,834
Vifor International Ltd. [Member] \| Regulatory Milestones [Member]
Potential milestone payment	$ 50,000
Percentage of premium on common stock investment	20.00%
Stock issuance price measurement period	30 days

The amount of potential milestone payment of common stock investment.

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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Period Type:	duration

- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

+ Details

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Period Type:	instant

- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

+ Details

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Period Type:	instant

- Details

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- Details

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