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Real Estate Investments - Textual (Details) $ in Thousands |  | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Feb. 02, 2021 USD ($) | Mar. 31, 2021 USD ($) a parcel | Mar. 31, 2020 USD ($) | Dec. 31, 2020 USD ($) a parcel | Feb. 02, 2021 ft² | Feb. 02, 2021 a
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |
Investment in joint venture |  | $ 415,823 |  | $ 389,811 |  |
Net gain on sale of undepreciated real estate |  | 1,993 | $ 0 |  |  |
Assets held for sale, net |  | 7,349 |  | 7,349 |  |
Other - Land | Held-for-sale |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |
Assets held for sale, net |  | $ 7,300 |  | $ 7,300 |  |
Other - Land | Held-for-sale | Other |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |
Area of land (in acres) | a |  | 35.2 |  | 35.2 |  |
Number of parcels of land | parcel |  | 2 |  | 2 |  |
3025 JFK Venture |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |
Lease agreement term | 99 years |  |  |  |  |
Area of land (in acres) |  |  |  |  | 1 | 1
Investment in joint venture | $ 34,800 | $ 34,800 |  |  |  |
Net gain on sale of undepreciated real estate | $ 2,000 |  |  |  |  |

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