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Leases - Narrative (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Apr. 05, 2021 | Jun. 30, 2021 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Leases |  |  |  |  |
Lease liability |  |  | $ 13,550 |  |
Letter of credit for security deposit |  |  | 478 | $ 321 |
Increase in ROU asset |  | $ 3,783 |  |  |
Right-of-use assets obtained in exchange for financing lease liabilities |  |  | 609 | 0 | $ 429
Rent expense |  |  | $ 3,390 | $ 2,644 | $ 2,160
Operating lease liabilities |  | $ 3,783 |  |  |
Minimum |  |  |  |  |
Leases |  |  |  |  |
Finance lease, remaining lease term |  |  | 1 year |  |
Maximum |  |  |  |  |
Leases |  |  |  |  |
Finance lease, remaining lease term |  |  | 5 years |  |
Office space, Cambridge, MA, Leased |  |  |  |  |
Leases |  |  |  |  |
Renewal term |  |  | 5 years |  |
Office Space Expansion Cambridge Ma |  |  |  |  |
Leases |  |  |  |  |
Renewal term | 5 years |  |  |  |
Operating lease term of contract | 5 years |  |  |  |
Lease liability | $ 4,983 |  |  |  |
Letter of credit for security deposit | 157 |  |  |  |
Tenant improvement allowance | $ 51 |  |  |  |

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- Definition The amount of allowance granted and reimbursable by the landlord to a tenant to entice tenant to move into landlord's building which will enable the tenant to prepare the leased premises for tenants occupancy. + References No definition available. + Details
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