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Mortgages and Other Loans Payable - Schedule of Mortgages and Other Loans Payable (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Debt Instrument [Line Items] |  |
Total fixed rate debt | $ 1,667,249 | $ 1,587,474
Total floating rate debt | 376,153 | 363,550
Total mortgages and other loans payable | 2,043,402 | 1,951,024
Deferred financing costs, net of amortization | (7,580) | (6,389)
Total mortgages and other loans payable, net | 2,035,822 | 1,944,635
100 Church Street |  |
Debt Instrument [Line Items] |  |
Total fixed rate debt | 370,000 | 370,000
7 Dey / 185 Broadway |  |
Debt Instrument [Line Items] |  |
Total fixed rate debt | 190,149 | 190,148
10 East 53rd Street |  |
Debt Instrument [Line Items] |  |
Total fixed rate debt | 204,775 | 205,000
Landmark Square |  |
Debt Instrument [Line Items] |  |
Total fixed rate debt | 100,000 | 100,000
485 Lexington Avenue |  |
Debt Instrument [Line Items] |  |
Total fixed rate debt | 450,000 | 450,000
500 Park Avenue |  |
Debt Instrument [Line Items] |  |
Total fixed rate debt | 80,000 | 0
420 Lexington Avenue |  |
Debt Instrument [Line Items] |  |
Total fixed rate debt | 272,325 | 272,326
100 Park Avenue |  |
Debt Instrument [Line Items] |  |
Total floating rate debt | 376,153 | 360,000
CMBS Repurchase Facility |  |
Debt Instrument [Line Items] |  |
Total floating rate debt | $ 0 | $ 3,550
Weighted Average | 100 Church Street |  |
Debt Instrument [Line Items] |  |
Interest rate, fixed rate debt (as a percent) | 5.89% |
Weighted Average | 7 Dey / 185 Broadway |  |
Debt Instrument [Line Items] |  |
Interest rate, fixed rate debt (as a percent) | 6.65% |
Weighted Average | 10 East 53rd Street |  |
Debt Instrument [Line Items] |  |
Interest rate, fixed rate debt (as a percent) | 5.37% |
Weighted Average | Landmark Square |  |
Debt Instrument [Line Items] |  |
Interest rate, fixed rate debt (as a percent) | 4.90% |
Weighted Average | 485 Lexington Avenue |  |
Debt Instrument [Line Items] |  |
Interest rate, fixed rate debt (as a percent) | 4.25% |
Weighted Average | 500 Park Avenue |  |
Debt Instrument [Line Items] |  |
Interest rate, fixed rate debt (as a percent) | 6.57% |
Weighted Average | 420 Lexington Avenue |  |
Debt Instrument [Line Items] |  |
Interest rate, fixed rate debt (as a percent) | 8.24% |
Weighted Average | 100 Park Avenue |  |
Debt Instrument [Line Items] |  |
Interest rate, floating rate debt (as a percent) | 2.37% |

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