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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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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