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Mortgages and Other Loans Payable - Schedule of Mortgages and Other Loans Payable (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Debt Instrument [Line Items] |  |
Total fixed rate debt | $ 1,587,474 | $ 1,387,386
Total floating rate debt | 363,550 | 110,000
Total mortgages and other loans payable | 1,951,024 | 1,497,386
Deferred financing costs, net of amortization | (6,389) | (6,067)
Total mortgages and other loans payable, net | 1,944,635 | 1,491,319
10 East 53rd Street |  |
Debt Instrument [Line Items] |  |
Total fixed rate debt | 205,000 | 0
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 | 190,148 | 190,148
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
420 Lexington Avenue |  |
Debt Instrument [Line Items] |  |
Total fixed rate debt | 272,326 | 277,238
CMBS Repurchase Facility |  |
Debt Instrument [Line Items] |  |
Total floating rate debt | 3,550 | 0
100 Park Avenue |  |
Debt Instrument [Line Items] |  |
Total floating rate debt | 360,000 | 0
690 Madison Avenue |  |
Debt Instrument [Line Items] |  |
Total floating rate debt | 0 | 60,000
719 Seventh Avenue |  |
Debt Instrument [Line Items] |  |
Total floating rate debt | $ 0 | $ 50,000
Weighted Average | 10 East 53rd Street |  |
Debt Instrument [Line Items] |  |
Interest rate, fixed rate debt (as a percent) | 5.45% |
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 | 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 | 420 Lexington Avenue |  |
Debt Instrument [Line Items] |  |
Interest rate, fixed rate debt (as a percent) | 8.24% |
Weighted Average | CMBS Repurchase Facility |  |
Debt Instrument [Line Items] |  |
Interest rate, floating rate debt (as a percent) | 1.75% |
Weighted Average | 100 Park Avenue |  |
Debt Instrument [Line Items] |  |
Interest rate, floating rate debt (as a percent) | 2.25% |

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