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COVID-19 Pandemic - Narrative (Details) ft² in Thousands, $ in Thousands | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2020 USD ($) | Sep. 30, 2020 USD ($) | Sep. 30, 2019 USD ($) | Sep. 10, 2020 ft² | Dec. 31, 2019 USD ($)
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Deferred leasing costs | $ 38,097 | $ 38,097 |  |  | $ 41,123
Reduction of rental revenues |  | 4,122 | $ 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 | $ 3,100 | 4,122 |  |  |
Write-off of rent receivable | $ 6,590 | 10,837 |  |  |
Office | 731 Lexington Avenue | 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 | 87.00% |  |  |  |
Rent collected & deferred, percent | 89.00% |  |  |  |
Residential | Alexander Apartment Tower | COVID-19 |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Rent collected, percent | 97.00% |  |  |  |
Century 21 | COVID-19 |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Reduction of rental revenues | $ 2,716 | 2,716 |  |  |
Write-off of rent receivable | 5,919 | 5,919 |  |  |
Century 21 | Rego Park II |  |  |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |  |  |
Area of property (in sqft.) | ft² |  |  |  | 135 |
Annualized revenue |  | 6,400 |  |  |
Deferred leasing costs | $ 1,619 | $ 1,619 |  |  |

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