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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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Description of reference rate used for variable rate of 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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The aggregate amount of the participation liability at the end of the accounting period.

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Mortgages Payable - Summary of Outstanding Mortgages Payable (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Apr. 07, 2021	Dec. 31, 2020
Mortgage Loans on Real Estate
Deferred debt issuance costs, net of accumulated amortization of $14,551 and $13,034 respectively	$ (6,931)
Notes Payable (in US dollars)	1,089,613		$ 1,156,170
Mortgages
Mortgage Loans on Real Estate
Notes payable, gross	1,096,544		1,164,544
Deferred debt issuance costs, net of accumulated amortization of $14,551 and $13,034 respectively	(6,931)		(8,374)
Notes Payable (in US dollars)	1,089,613		1,156,170
Deferred debt issuance costs, accumulated amortization	$ 14,551		13,034
Mortgages \| 731 Lexington Avenue \| Office space
Mortgage Loans on Real Estate
Interest rate	0.0101%
Notes payable, gross	$ 500,000		500,000
Debt instrument, description of variable rate basis	LIBOR
Mortgages \| 731 Lexington Avenue \| Office space \| LIBOR
Mortgage Loans on Real Estate
Basis spread over LIBOR	0.90%
Mortgages \| 731 Lexington Avenue \| Retail space
Mortgage Loans on Real Estate
Interest rate	0.0172%
Notes payable, gross	$ 300,000		300,000
Mortgages \| Rego Park II \| Retail space
Mortgage Loans on Real Estate
Interest rate	0.0145%
Notes payable, gross	$ 202,544		202,544
Debt instrument, description of variable rate basis	LIBOR
Mortgages \| Rego Park II \| Retail space \| Participation Agreement
Mortgage Loans on Real Estate
Notes Payable (in US dollars)		$ 202,544	252,544
Loan participation balance			50,000
Mortgages \| Rego Park II \| Retail space \| LIBOR
Mortgage Loans on Real Estate
Basis spread over LIBOR	1.35%
Mortgages \| The Alexander apartment tower \| Retail space
Mortgage Loans on Real Estate
Interest rate	0.0263%
Notes payable, gross	$ 94,000		94,000
Mortgages \| Paramus
Mortgage Loans on Real Estate
Notes payable, gross	$ 0		$ 68,000