Represents the number of renewal options.

No definition available.

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- Definition

Amount of lease cost recognized by lessee for lease contract.

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Period Type:	duration

- References

No definition available.

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- Definition

Indicates (true false) whether lessee has option to extend operating lease.

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- Definition

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

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- Definition

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

+ References

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of operating lease expense. Excludes sublease income.

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- Definition

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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Weighted average discount rate for operating lease calculated at point in time.

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- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

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.

+ References

No definition available.

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- Definition

Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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Commitments and Contingencies (Details) $ in Thousands	1 Months Ended	3 Months Ended
Commitments and Contingencies (Details) $ in Thousands	Feb. 28, 2018 USD ($) item	Mar. 31, 2020 USD ($)	Mar. 31, 2015
Lease Cost:
Operating lease cost		$ 344
Variable lease cost		168
Total lease cost		512
Operating cash flows used for operating leases		$ 353
Weighted average remaining lease term		3 years 6 months
Weighted average incremental borrowing rate		6.47%
620 Memorial Drive, Cambridge MA
Leased assets
Term of lease			5 years
Option to extend the term	true
Number of renewal options \| item	1
Renewal term	5 years
620 Memorial Drive, Cambridge MA \| Minimum
Leased assets
Rent for facility lease	$ 1,400
620 Memorial Drive, Cambridge MA \| Maximum
Leased assets
Rent for facility lease	$ 1,700