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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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