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Mortgages Payable - Schedule of Outstanding Mortgages Payable (Details) - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2026 | Jun. 30, 2025 | Dec. 31, 2025
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |
Notes Payable | $ 834,572 |  | $ 829,451
PIK interest expense | 3,832 | $ 0 |
Mortgages |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |
Notes payable, gross | 840,522 |  | 836,691
Deferred debt issuance costs, net of accumulated amortization of $6,551 and $5,263, respectively | (5,950) |  | (7,240)
Deferred debt issuance costs, accumulated amortization | $ 6,551 |  | 5,263
Mortgages | 731 Lexington Avenue | Office Space |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |
Interest rate | 5.04% |  |
Notes payable, gross | $ 400,000 |  | 400,000
Mortgages | 731 Lexington Avenue | Retail Space |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |
Interest rate | 4.55% |  |
Notes payable, gross | $ 171,522 |  | 167,691
PIK interest expense | $ 4,022 |  | 191
Mortgages | Rego Park shopping center | Retail Space |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |
Interest rate | 5.62% |  |
Notes payable, gross | $ 175,000 |  | 175,000
Rate spread | 2.00% |  |
Mortgages | Rego Park shopping center | Retail Space | Maximum |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |
Rate spread | 4.50% |  |
Mortgages | The Alexander apartment tower | Retail Space |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |
Interest rate | 2.63% |  |
Notes payable, gross | $ 94,000 |  | $ 94,000

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