Commitments and contingencies - Operating Leases - (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Aug. 31, 2023
Commitments and Contingencies
Lease asset liability	$ 136
New Corporate Headquarters Lease
Commitments and Contingencies
Term of contract			3 years
Renewal term			2 years
Rental expense	100	$ 29
Operating lease cash payments	$ 100	$ 28
Operating lease discount rate	11.00%	11.00%
Former Corporate Headquarters Lease
Commitments and Contingencies
Rental expense	$ 0	$ 22
Operating lease cash payments	$ 0	$ 22

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
-Topic 842
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- Definition

Discount rate used by lessee to determine present value of operating lease payments.

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Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of operating lease expense. Excludes sublease income.

+ References

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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