Income taxes - Cash Paid for Income Taxes, Net of Refunds Received (Details) $ in Thousands	12 Months Ended
Mar. 31, 2026 USD ($)
Income taxes [Abstract]
Federal	$ 0
Cash paid for income taxes, net of refunds received	12
New Jersey [Member]
Income taxes [Abstract]
State	8
California [Member]
Income taxes [Abstract]
State	4
Pennsylvania [Member]
Income taxes [Abstract]
State	0
Other States [Member]
Income taxes [Abstract]
State	$ 0

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Amount, after income tax refund received, of cash paid to federal (national) tax jurisdiction for tax on income.

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Amount, after income tax refund received, of cash paid to state and local tax jurisdictions for tax on income.

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Amount, after refund, of cash paid to foreign, federal, state, and local jurisdictions as income tax.

+ References

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