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v3.22.1

Subsequent Events (Details) $ in Thousands |  |  |  |  |  | 3 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Apr. 28, 2022 ft² | Apr. 18, 2022 USD ($) ft² | Apr. 14, 2022 USD ($) ft² | Apr. 07, 2022 USD ($) a ft² | Apr. 19, 2021 USD ($) a ft² | Mar. 31, 2022 USD ($) | Mar. 31, 2021 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Interest and Other Income |  |  |  |  |  | $ 1,228 | $ 1,168 |  |
Secured Debt |  |  |  |  |  | 3,268,745 |  | $ 3,267,914 |
Cash held in escrows |  |  |  |  |  | $ 46,072 | $ 251,814 | $ 48,466 | $ 50,587
11251 Roger Bacon Drive |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  |  |  |  | 65,000 |  |  |  |
Area of Land | a |  |  |  |  | 2.6 |  |  |  |
Asset Acquisition, Price of Acquisition, Expected |  |  |  |  | $ 5,600 |  |  |  |
Subsequent Event [Member] | 11251 Roger Bacon Drive |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Interest and Other Income |  |  |  | $ 6,900 |  |  |  |  |
Net Rentable Area (in sf) | ft² |  |  |  | 65,000 |  |  |  |  |
Area of Land | a |  |  |  | 2.6 |  |  |  |  |
Subsequent Event [Member] | Madison Centre |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  |  | 760,000 |  |  |  |  |  |
Asset Acquisition, Price of Acquisition, Expected |  |  | $ 730,000 |  |  |  |  |  |
Number of floors |  |  | 37 |  |  |  |  |  |
Cash held in escrows |  |  | $ 50,000 |  |  |  |  |  |
Subsequent Event [Member] | Hub50House [Member] |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Ownership Percentage |  | 50.00% |  |  |  |  |  |  |
Secured Debt |  | $ 176,500 |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  | 2.00% |  |  |  |  |  |  |
Debt Instrument, Maturity Date |  | Jun. 19, 2022 |  |  |  |  |  |  |
Subsequent Event [Member] | Hub50House [Member] | Residential Building |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  | 320,000 |  |  |  |  |  |  |
Number of Units in Real Estate Property |  | 440 |  |  |  |  |  |  |
Subsequent Event [Member] | 290 Binney Street |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² | 570,000 |  |  |  |  |  |  |  |
Subsequent Event [Member] | Kendall Center future development | Scenario, Plan |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² | 1,100,000 |  |  |  |  |  |  |  |
Number of buildings | 2 |  |  |  |  |  |  |  |
Subsequent Event [Member] | Kendall Center future development | Residential Building | Scenario, Plan |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² | 400,000 |  |  |  |  |  |  |  |

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