Leases - Schedule of Future minimum lease payments (Details) - Accounting Standards Update 2016-02 [Member] $ in Thousands	Dec. 31, 2023 USD ($)
26 Landsdowne Street [Member]
Related Party Transaction [Line Items]
2024	$ 2,572
2025	2,649
2026	2,729
2027	2,811
Thereafter	1,426
Total minimum lease payments	12,187
Less: imputed interest	(1,575)
Total lease liability	10,612
125 Sidney Street [Member]
Related Party Transaction [Line Items]
2024	210
Total minimum lease payments	210
Less: imputed interest	(1)
Total lease liability	$ 209

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
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Present value of lessee's discounted obligation for lease payments from operating lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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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.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
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