Commitments and Contingencies - Additional Information (Detail) - USD ($)	Mar. 31, 2020	Mar. 31, 2019
Other Commitments [Line Items]
Contingent liabilities	$ 0
Future commitments	72,200,000
Commitments expected to be incurred in fiscal 2020	40,000,000.0
Commitments expected to be incurred beyond fiscal 2020	32,200,000
Technology License Commitments
Other Commitments [Line Items]
Accrued milestone payments		$ 0
Technology License Commitments \| ARO-ENaC Program
Other Commitments [Line Items]
Accrued milestone payments	$ 900,000

Accrued milestone payments.

No definition available.

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- Definition

Amount of loss contingency liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14326-108349

+ Details

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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.

+ References

No definition available.

+ Details

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- Definition

Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

+ References

No definition available.

+ Details

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- Definition

Minimum amount of purchase arrangement maturing in the second fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

+ Details

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- Definition

Minimum amount of purchase arrangement maturing in the remainder of the fiscal year following the latest fiscal year ended. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

+ Details

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