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Real Estate Sales - Narrative (Details) - USD ($) $ in Thousands |  |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | --- | ---
Oct. 04, 2021 | Jun. 04, 2021 | Dec. 31, 2021 | Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Real Estate [Line Items] |  |  |  |  |  |  |
Proceeds from sale of land |  |  |  |  |  | $ 9,291 | $ 0
Gains on sale of real estate |  |  |  | $ 0 | $ 0 | $ 9,124 | $ 0
Bronx Land Parcel |  |  |  |  |  |  |
Real Estate [Line Items] |  |  |  |  |  |  |
Proceeds from sale of land, excluding disposal cost |  | $ 10,000 |  |  |  |  |
Proceeds from sale of land |  | 9,291 |  |  |  |  |
Gains on sale of real estate |  | $ 9,124 |  |  |  |  |
IKEA | Tenant Occupant | Paramus | Forecast |  |  |  |  |  |  |
Real Estate [Line Items] |  |  |  |  |  |  |
Gains on sale of real estate |  |  | $ 60,826 |  |  |  |
IKEA | Tenant Occupant | Paramus | Subsequent Event |  |  |  |  |  |  |
Real Estate [Line Items] |  |  |  |  |  |  |
Proceeds from sale of land, excluding disposal cost | $ 75,000 |  |  |  |  |  |
Proceeds from sale of land | 68,000 |  |  |  |  |  |
Net proceeds from sale of land | $ 4,580 |  |  |  |  |  |

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