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Number of additional renewal terms.

+ References

No definition available.

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- Definition

Amount of incentive received by lessee from lessor.

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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.

+ Details

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Description of terms and conditions of option to extend lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability.

+ References

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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.

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Indicates (true false) whether sublessee has option to extend operating sublease.

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- Definition

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

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

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Leases - Additional Information (Detail) $ in Thousands	1 Months Ended						12 Months Ended
Leases - Additional Information (Detail) $ in Thousands	Jul. 31, 2020 USD ($) Term	May 31, 2020 Term	Dec. 31, 2019	May 31, 2019	May 31, 2016	Jun. 30, 2015	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Lessee Lease Description [Line Items]
Operating lease, right-of-use asset							$ 174,460	$ 50,865
Operating lease liability							$ 225,030	$ 61,429
2015 Lease [Member]
Lessee Lease Description [Line Items]
Lease commencement date						Nov. 15, 2015
Lessee, operating lease, existence of option to extend						false
Lessee, operating lease, option to extend							expires in 2022 with no further option to extend
Lease expiration year						2022
2016 Sublease [Member]
Lessee Lease Description [Line Items]
Lease commencement date					Dec. 23, 2016
Lease expiration year					2022
2019 Lease [Member]
Lessee Lease Description [Line Items]
Lease commencement date				Jun. 01, 2019
Lessee, operating lease, existence of option to extend				true
Lessee, operating lease, option to extend							an option to extend the term of the lease for an additional five-year period based on certain conditions within the Company’s control.
Lease expiration, month and year				2026-11
Extended term of lease expiration				5 years
2019 Sublease [Member]
Lessee Lease Description [Line Items]
Lessee, operating lease, option to extend							expires in 2022 with no further option to extend
Lease expiration year			2022
Framingham Lease [Member]
Lessee Lease Description [Line Items]
Lease expiration, month and year		2036-03
Lessee, operating sublease, existence of option to extend		true
Number of additional renewal terms \| Term		2
Lease renewal term under each extension option		7 years
2020 Boston Lease [Member]
Lessee Lease Description [Line Items]
Lessee, operating lease, existence of option to extend	true
Lessee, operating lease, option to extend							an option to extend the term of the lease for two additional five-year periods
Lease expiration, month and year	2034-03
Extended term of lease expiration	5 years
Number of additional renewal terms \| Term	2
Operating lease, right-of-use asset	$ 149,800
Operating lease liability	147,900
Tenant incentives	$ 49,200