Commitments and contingencies - Additional information (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Mar. 31, 2023
Lessee, Lease, Description [Line Items]
Finance Lease Costs	$ 607	$ 607	$ 1,214	$ 1,214
Operating lease costs	281	252	561	511
Minimum payments committed to manufacturing organization	1,000		1,000		$ 1,000
Research and development
Lessee, Lease, Description [Line Items]
Finance Lease Costs	607	518	1,214	1,035
Operating lease costs	228	103	457	213
Selling, general and administrative
Lessee, Lease, Description [Line Items]
Finance Lease Costs	0	89	0	179
Operating lease costs	$ 53	$ 149	$ 104	$ 298

Amount of amortization expense attributable to right-of-use asset from finance lease.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
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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

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-Topic 842
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-Name Accounting Standards Codification
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-Paragraph 3
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-URI https://asc.fasb.org//1943274/2147478964/842-20-50-3

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

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- Definition

Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations.

+ References

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