v3.19.3.a.u2

Leases (Details) $ in Thousands | 1 Months Ended | 6 Months Ended | 12 Months Ended |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Apr. 30, 2017 USD ($) | Aug. 31, 2015 USD ($) ft² | Dec. 31, 2018 USD ($) ft² | Dec. 31, 2019 USD ($) ft² campus | Dec. 31, 2018 USD ($) ft² | Dec. 31, 2017 USD ($) | Dec. 01, 2020 USD ($) | Aug. 31, 2019 USD ($) ft² | Feb. 28, 2019 ft² extension_period | Jan. 01, 2019 USD ($) | Aug. 31, 2016 USD ($) ft² extension_period | May 31, 2016 USD ($) ft² extension_period $ / ft²
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Rent expense |  |  |  |  | $ 19,100 | $ 18,600 |  |  |  |  |  |
Number of campuses | campus |  |  |  | 2 |  |  |  |  |  |  |  |
Property and equipment, net |  |  | $ 211,977 |  | 211,977 |  |  |  |  | $ 209,494 |  |
Carrying value of the construction financing obligation |  |  | $ 33,489 |  | $ 33,489 |  |  |  |  |  |  |
Amounts representing interest or imputed interest, operating lease |  |  |  | $ 75,750 |  |  |  |  |  |  |  |
Amounts representing interest or imputed interest, finance lease |  |  |  | $ 255,759 |  |  |  |  |  |  |  |
Imputed interest rate |  |  |  | 17.20% |  |  |  |  |  |  |  |
Cambridge Leases |  |  |  |  |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Area of office space (in sqft) | ft² |  |  |  | 200,000 |  |  |  |  |  |  |  |
Norwood Leases |  |  |  |  |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Area of office space (in sqft) | ft² |  |  |  |  |  |  |  |  | 200,000 |  |  |
Finance lease, term of lease |  |  |  |  |  |  |  |  |  |  | 35 years |
Extension term |  |  |  |  |  |  |  |  | 5 years |  | 10 years |
Percentage subleased |  |  |  |  |  |  |  |  | 64.00% |  |  |
Number of extension periods | extension_period |  |  |  |  |  |  |  |  | 4 |  | 2 |
200 Technology Square | Cambridge Leases |  |  |  |  |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Area of office space (in sqft) | ft² |  |  |  |  |  |  |  | 50,000 |  |  |  | 124,760
Tenant allowance (in usd per sqft) | $ / ft² |  |  |  |  |  |  |  |  |  |  |  | 10.00
Security deposit |  |  |  |  |  |  |  |  |  |  |  | $ 1,900
Extension term |  |  |  |  |  |  |  | 2 years |  |  |  | 5 years
Tenant improvement allowance |  |  |  |  |  |  |  | $ 3,500 |  |  |  |
Lease term |  |  |  |  |  |  |  |  |  |  |  | 11 years
Number of extension periods | extension_period |  |  |  |  |  |  |  |  |  |  |  | 2
200 Technology Square, Sublease Agreements | Cambridge Leases |  |  |  |  |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Area of office space (in sqft) | ft² |  |  | 34,268 |  | 34,268 |  |  |  |  |  |  |
500 Technology Square | Cambridge Leases |  |  |  |  |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Area of office space (in sqft) | ft² |  | 61,618 |  |  |  |  |  | 60,000 |  |  |  |
Rate per annum |  | $ 3,900 |  |  |  |  |  |  |  |  |  |
Security deposit |  | 1,000 |  |  |  |  |  |  |  |  |  |
Tenant improvement allowance |  | $ 3,100 |  |  |  |  |  |  |  |  |  |
Lease term |  | 6 years |  |  |  |  |  |  |  |  |  |
Land adjacent to Norwood | Norwood Leases |  |  |  |  |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Rate per annum | $ 300 |  |  |  |  |  |  |  |  |  |  |
Lease term | 35 years |  |  |  |  |  |  |  |  |  |  |
Office, laboratory, and light manufacturing space | Norwood Leases |  |  |  |  |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Area of office space (in sqft) | ft² |  |  |  |  |  |  |  |  |  |  | 200,000 |
Security deposit |  |  |  | $ 8,900 |  |  |  |  |  |  |  |
Tenant improvement allowance |  |  |  |  |  |  |  |  |  |  | $ 24,200 |
Carrying value of the construction financing obligation |  |  | $ 33,500 |  | $ 33,500 | 15,700 |  |  |  |  |  |
Financing obligation in accrued liabilities |  |  | 10,500 |  | 10,500 | 14,500 |  |  |  |  |  |
Amounts representing interest or imputed interest, operating lease |  |  |  | 10,300 |  |  |  |  |  |  |  |
Amounts representing interest or imputed interest, finance lease |  |  |  | $ 208,500 |  |  |  |  |  |  |  |
Scenario, Forecast | 200 Technology Square | Cambridge Leases |  |  |  |  |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Security deposit |  |  |  |  |  |  | $ 2,200 |  |  |  |  |
Construction in progress | Office, laboratory, and light manufacturing space | Norwood Leases |  |  |  |  |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Property and equipment, net |  |  | 86,400 |  | $ 86,400 | $ 75,000 |  |  |  |  |  |
Transfers of property and equipment |  |  | 161,600 |  |  |  |  |  |  |  |  |
Building | Office, laboratory, and light manufacturing space | Norwood Leases |  |  |  |  |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Transfers of property and equipment |  |  | $ 140,400 |  |  |  |  |  |  |  |  |

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- Definition This element represents the payments that the lessee is obligated to make or can be required to make in connection with a property under the terms of an agreement classified as an operating lease, excluding contingent rentals and a guarantee by the lessee of the lessor's debt and the lessee's obligation to pay (apart from the rental payments) executory costs such as insurance, maintenance, and taxes. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 25 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=77910348&loc=d3e34039-112682 Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 55 -Paragraph 40 -Subparagraph (Note 3) -URI http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697 Reference 3: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717 + Details
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