Leases - Schedule of Minimum rental commitments under non-cancelable leases (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
ASC 840 [Member]
Related Party Transaction [Line Items]
2022		$ 613
2023		836
2024		210
Total minimum lease payments		1,659
26 Landsdowne Street \| Accounting Standards Update 2016-02 [Member]
Related Party Transaction [Line Items]
Total minimum lease payments	$ 15,298
26 Landsdowne Street \| ASC 840 [Member]
Related Party Transaction [Line Items]
2022		2,424
2023		2,497
2024		2,572
2025		2,649
2026		2,729
Thereafter		4,237
Total minimum lease payments		$ 17,108
125 Sidney Street \| Accounting Standards Update 2016-02 [Member]
Related Party Transaction [Line Items]
Total minimum lease payments	$ 1,250

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918701-209980

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Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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