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COVID-19 Pandemic - Narrative (Details) ft² in Thousands, $ in Thousands | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2020 | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Sep. 10, 2020 ft²
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Reduction of rental revenues |  | $ 4,122 | $ 0 | $ 0 |
COVID-19 |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Rent collected, percent | 95.00% |  |  |  |
Rent collected & deferred, percent | 96.00% |  |  |  |
Reduction of rental revenues |  | 4,122 |  |  |
Write-off of rent receivable |  | 10,837 |  |  |
Office | COVID-19 |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Rent collected, percent | 100.00% |  |  |  |
Retail | COVID-19 |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Rent collected, percent | 90.00% |  |  |  |
Rent collected & deferred, percent | 91.00% |  |  |  |
Residential | COVID-19 |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Rent collected, percent | 98.00% |  |  |  |
Century 21 | COVID-19 |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Reduction of rental revenues |  | 2,716 |  |  |
Write-off of rent receivable |  | 5,919 |  |  |
Century 21 | Rego Park II |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Area of property (in square feet) | ft² |  |  |  |  | 135
Annualized revenue |  | $ 6,400 |  |  |

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