Fair value measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - Fair Value on a Recurring Basis [Member] - USD ($) $ in Thousands	Mar. 31, 2025	Mar. 31, 2024
Assets
Total assets	$ 21,304	$ 19,725
Liabilities
Derivative warrant liabilities	1,141	4,359
Total liabilities	1,141	4,359
Quoted Prices in Active Markets (Level 1) [Member]
Assets
Total assets	21,304	19,725
Liabilities
Derivative warrant liabilities	0	0
Total liabilities	0	0
Significant Other Observable Inputs (Level 2) [Member]
Assets
Total assets	0	0
Liabilities
Derivative warrant liabilities	0	0
Total liabilities	0	0
Significant Unobservable Inputs (Level 3) [Member]
Assets
Total assets	0	0
Liabilities
Derivative warrant liabilities	1,141	4,359
Total liabilities	1,141	4,359
Treasury Bills Classified as Cash Equivalents [Member]
Assets
Cash and cash equivalents	21,304
Treasury Bills Classified as Cash Equivalents [Member] \| Quoted Prices in Active Markets (Level 1) [Member]
Assets
Cash and cash equivalents	21,304
Treasury Bills Classified as Cash Equivalents [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Assets
Cash and cash equivalents	0
Treasury Bills Classified as Cash Equivalents [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Assets
Cash and cash equivalents	$ 0
Guaranteed Investment Certificates and Term Deposits Classified as Cash Equivalents [Member]
Assets
Cash and cash equivalents		19,725
Guaranteed Investment Certificates and Term Deposits Classified as Cash Equivalents [Member] \| Quoted Prices in Active Markets (Level 1) [Member]
Assets
Cash and cash equivalents		19,725
Guaranteed Investment Certificates and Term Deposits Classified as Cash Equivalents [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Assets
Cash and cash equivalents		0
Guaranteed Investment Certificates and Term Deposits Classified as Cash Equivalents [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Assets
Cash and cash equivalents		$ 0

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- Definition

Fair value portion of asset recognized for present right to economic benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483466/210-20-50-3

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- References

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- Definition

Fair value of financial and nonfinancial obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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