Stock-based compensation - Assumptions to determine grant-date fair value of stock options (Details) - Stock options |
3 Months Ended | 6 Months Ended | ||
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Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Stock-Based Compensation | ||||
| Risk-free interest rate | 4.61% | 4.00% | 4.12% | 3.97% |
| Expected term (in years) | 6 years 1 month 6 days | 6 years 1 month 6 days | 6 years | 6 years |
| Expected volatility | 124.10% | 83.90% | 109.00% | 76.50% |
| Expected dividend yield | 0.00% | 0.00% | 0.00% | 0.00% |
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The minimum risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Rate of weighted-average expected volatility for award under share-based payment arrangement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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