Notes payable gross.

No definition available.

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- Definition

The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of accumulated amortization of debt issuance costs.

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- Definition

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

+ References

No definition available.

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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- Definition

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

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

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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- Definition

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 (Outstanding mortgages payable) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Oct. 02, 2018
Mortgage Loans on Real Estate
Document Period End Date	Dec. 31, 2019
Deferred debt issuance costs, net of accumulated amortization of $14,362 and $9,212, respectively	$ (3,875)
Notes Payable (in US dollars)	970,961	$ 965,826
Paramus, NJ
Mortgage Loans on Real Estate
Interest rate			2.90%
Mortgages
Mortgage Loans on Real Estate
Notes payable, gross	974,836	974,836
Deferred debt issuance costs, net of accumulated amortization of $14,362 and $9,212, respectively	(3,875)	(9,010)
Notes Payable (in US dollars)	970,961	965,826
Deferred debt issuance costs, accumulated amortization	$ 14,362	9,212
Mortgages \| Paramus, NJ
Mortgage Loans on Real Estate
Maturity date	Oct. 01, 2021
Interest rate	4.72%
Notes payable, gross	$ 68,000	68,000
Mortgages \| 731 Lexington Avenue \| Retail space
Mortgage Loans on Real Estate
Maturity date	Aug. 01, 2022
Interest rate	3.10%
Notes payable, gross	$ 350,000	350,000
Debt instrument, description of variable rate basis	LIBOR
Mortgages \| 731 Lexington Avenue \| Retail space \| LIBOR
Mortgage Loans on Real Estate
Basis spread over LIBOR	1.40%
Mortgages \| 731 Lexington Avenue \| Office space
Mortgage Loans on Real Estate
Maturity date	Jun. 01, 2024
Interest rate	2.64%
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 \| Rego Park II \| Retail space
Mortgage Loans on Real Estate
Maturity date	Dec. 01, 2025
Interest rate	3.15%
Notes payable, gross	$ 56,836	$ 56,836
Debt instrument, description of variable rate basis	LIBOR
Mortgages \| Rego Park II \| Retail space \| LIBOR
Mortgage Loans on Real Estate
Basis spread over LIBOR	1.35%
Participation Agreement \| Rego Park II
Mortgage Loans on Real Estate
Loan participation balance	$ 195,708