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, 2026	Mar. 31, 2025
Fair value measurements [Abstract]
Total assets	$ 15,670	$ 21,304
Derivative warrant liabilities		1,141
Total liabilities	0	1,141
Quoted Prices in Active Markets (Level 1) [Member]
Fair value measurements [Abstract]
Total assets	15,670	21,304
Derivative warrant liabilities		0
Total liabilities	0	0
Significant Other Observable Inputs (Level 2) [Member]
Fair value measurements [Abstract]
Total assets	0	0
Derivative warrant liabilities		0
Total liabilities	0	0
Significant Unobservable Inputs (Level 3) [Member]
Fair value measurements [Abstract]
Total assets	0	0
Derivative warrant liabilities		1,141
Total liabilities	0	1,141
Treasury Bills Classified as Cash Equivalents [Member]
Fair value measurements [Abstract]
Cash and cash equivalents	15,670	21,304
Treasury Bills Classified as Cash Equivalents [Member] \| Quoted Prices in Active Markets (Level 1) [Member]
Fair value measurements [Abstract]
Cash and cash equivalents	15,670	21,304
Treasury Bills Classified as Cash Equivalents [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Fair value measurements [Abstract]
Cash and cash equivalents	0	0
Treasury Bills Classified as Cash Equivalents [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Fair value measurements [Abstract]
Cash and cash equivalents	$ 0	$ 0

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

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
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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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/2003/role/disclosureRef
-Topic 825
-SubTopic 10
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-Subparagraph (b)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
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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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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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- Definition

Fair value of financial and nonfinancial obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
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