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Mortgages Payable - Schedule of Outstanding Mortgages Payable (Details) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2023 | Jun. 30, 2023 | Dec. 31, 2022
Mortgage Loans on Real Estate |  |  |
Deferred debt issuance costs, net of accumulated amortization of $17,639 and $16,071, respectively | $ (3,993) |  |
Notes payable | 1,092,551 |  | $ 1,091,051
Mortgages |  |  |
Mortgage Loans on Real Estate |  |  |
Deferred debt issuance costs, accumulated amortization | 17,639 |  | 16,071
Total | 1,096,544 |  | 1,096,544
Deferred debt issuance costs, net of accumulated amortization of $17,639 and $16,071, respectively | (3,993) |  | (5,493)
Notes payable | $ 1,092,551 |  | 1,091,051
Mortgages | 731 Lexington Avenue | Prime Rate |  |  |
Mortgage Loans on Real Estate |  |  |
Interest cap rate |  | 6.00% |
Basis spread | 8.50% |  |
Mortgages | 731 Lexington Avenue | Office space |  |  |
Mortgage Loans on Real Estate |  |  |
Interest rate | 6.00% |  |
Total | $ 500,000 |  | 500,000
Mortgages | 731 Lexington Avenue | Office space | Prime Rate |  |  |
Mortgage Loans on Real Estate |  |  |
Interest cap rate | 6.00% |  |
Mortgages | 731 Lexington Avenue | Retail space |  |  |
Mortgage Loans on Real Estate |  |  |
Interest rate | 1.76% |  |
Total | $ 300,000 |  | 300,000
Derivative, Swaption Interest Rate | 1.76% |  |
Mortgages | 731 Lexington Avenue | Retail space | SOFR |  |  |
Mortgage Loans on Real Estate |  |  |
Basis spread | 1.51% |  |
Mortgages | Rego Park II | Retail space |  |  |
Mortgage Loans on Real Estate |  |  |
Interest rate | 5.60% |  |
Total | $ 202,544 |  | 202,544
Mortgages | Rego Park II | Retail space | SOFR |  |  |
Mortgage Loans on Real Estate |  |  |
Interest cap rate | 4.15% |  |
Basis spread | 1.45% |  |
Mortgages | The Alexander apartment tower | Apartment Building |  |  |
Mortgage Loans on Real Estate |  |  |
Interest rate | 2.63% |  |
Total | $ 94,000 |  | $ 94,000

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