Nature of the business (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	6 Months Ended
Aug. 31, 2026	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Mar. 31, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Net loss		$ (57,121)	$ (83,100)	$ (126,887)	$ (169,793)
Accumulated deficit		$ 1,389,406		$ 1,389,406		$ 1,262,519
Proceeds from an equity offering	$ 141,000

Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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+ Details

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References

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+ Details