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Amount of accumulated amortization of debt issuance costs.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Interest paid other than in cash for example by issuing additional debt securities. As a noncash item, it is added to net income when calculating cash provided by or used in operations using the indirect method.

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Mortgages Payable - Schedule of Outstanding Mortgages Payable (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Notes Payable	$ 837,164		$ 829,451
PIK interest expense	5,779	$ 0
Mortgages
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Notes payable, gross	842,470		836,691
Deferred debt issuance costs, net of accumulated amortization of $7,195 and $5,263, respectively	(5,306)		(7,240)
Deferred debt issuance costs, accumulated amortization	$ 7,195		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	$ 173,470		167,691
PIK interest expense	$ 5,970		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	5.69%
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 \| Apartment Building
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