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Investments in Unconsolidated Joint Ventures - Schedule of Investments in Unconsolidated Joint Ventures Sold (Details) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
May 31, 2024 | Jan. 31, 2024 | Sep. 30, 2024 | Mar. 31, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | Dec. 31, 2023
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Loss on Sale |  |  | $ 371 |  | $ 0 | $ 19,006 | $ (79) |
Employee-related liabilities |  |  | 7,800 |  |  | 7,800 |  |
Carrying Value |  |  | 293,924 |  |  | 293,924 |  | $ 346,745
Depreciable real estate reserves and impairment |  |  | 0 |  | $ 389 | (65,839) | $ (305,527) |
Preferred Equity (4) |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Carrying Value |  |  | 134,474 |  |  | 134,474 |  |
625 Madison Avenue | Preferred Equity (4) |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Carrying Value |  |  | 209,900 |  |  | 209,900 |  |
625 Madison Avenue |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Depreciable real estate reserves and impairment |  |  |  | $ 5,900 |  |  |  |
625 Madison Avenue | Preferred Equity (4) |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Carrying value of investment in leasehold interest |  |  | $ 235,400 |  |  | $ 235,400 |  |
Average yield (as a percent) |  |  |  |  |  | 8.91% |  |
717 Fifth Avenue | Joint venture | Wharton Properties |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Ownership Interest Sold |  | 10.92% |  |  |  |  |  |
Gross Asset Valuation |  | $ 963,000 |  |  |  |  |  |
Loss on Sale |  | $ 24,900 |  |  |  |  |  |
625 Madison Avenue | Joint venture | Wharton Properties |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Ownership Interest Sold | 90.43% |  |  |  |  |  |  |
Gross Asset Valuation | $ 634,600 |  |  |  |  |  |  |
Loss on Sale | $ (7,600) |  |  |  |  |  |  |

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