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v3.20.2

Properties Held for Sale and Property Dispositions (Details) $ in Millions | 1 Months Ended
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Sep. 30, 2020 USD ($) ft² | May 31, 2020 USD ($) ft² | Mar. 31, 2020 USD ($) ft²
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |
Approximate Square Feet | ft² | 30,328,709 |  |
315 West 33rd Street |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |
Approximate Square Feet | ft² |  |  | 492,987
Sales Price |  |  | $ 446.5
Gain (loss) |  |  | $ 72.3
Accrued employee compensation in connection with realization of investment | $ 6.0 |  |
609 Fifth Avenue |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |
Approximate Square Feet | ft² |  | 21,437 |
Sales Price |  | $ 168.0 |
Gain (loss) |  | $ 65.4 |
Accrued employee compensation in connection with realization of investment | $ 2.0 |  |
400 East 58th Street |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |
Approximate Square Feet | ft² | 140,000 |  |
Sales Price | $ 62.0 |  |
Gain (loss) | $ 8.3 |  |

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