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COVID-19 Pandemic - Narrative (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 2020 | Jun. 30, 2019
Unusual or Infrequent Item, or Both [Line Items] |  |  |
Reduction of rental revenues |  | $ 1,022 | $ 0
COVID-19 |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |
Rent collected, percent | 89.00% |  |
Rent collected & deferred, percent | 92.00% |  |
Reduction of rental revenues | $ 1,022 | 1,022 |
Write-off of rent receivable | $ 4,247 | $ 4,247 |
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 | 76.00% |  |
Rent collected & deferred, percent | 83.00% |  |
Residential | Alexander Apartment Tower | COVID-19 |  |  |
Unusual or Infrequent Item, or Both [Line Items] |  |  |
Rent collected, percent | 96.00% |  |

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