Notes payable gross.

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- Definition

Percentage of cash mortgage collateralized

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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.

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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.

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

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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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Mortgages Payable (Outstanding mortgages payable) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Oct. 02, 2018	Dec. 31, 2017
Mortgage Loans on Real Estate
Deferred debt issuance costs, net of accumulated amortization of $9,212 and $6,315, respectively	$ (9,010)
Notes Payable (in US dollars)	$ 1,161,534		$ 1,240,222
Rego Park I
Mortgage Loans on Real Estate
Percentage of cash mortgage collateralized	100.00%
Paramus
Mortgage Loans on Real Estate
Interest rate		2.90%
Mortgages \| Rego Park II \| Retail space
Mortgage Loans on Real Estate
Interest rate	3.87%
Notes payable, gross			256,194
Mortgages \| Secured loan
Mortgage Loans on Real Estate
Notes payable, gross	$ 1,170,544		1,252,440
Deferred debt issuance costs, net of accumulated amortization of $9,212 and $6,315, respectively	(9,010)		(12,218)
Notes Payable (in US dollars)	1,161,534		1,240,222
Deferred debt issuance costs, accumulated amortization	$ 9,212		$ 6,315
Mortgages \| Secured loan \| Rego Park I
Mortgage Loans on Real Estate
Percentage of cash mortgage collateralized	100.00%		100.00%
Notes payable, gross	$ 0		$ 78,246
Mortgages \| Secured loan \| Paramus
Mortgage Loans on Real Estate
Maturity date	Oct. 05, 2021
Interest rate	4.72%
Notes payable, gross	$ 68,000		68,000
Mortgages \| Secured loan \| Rego Park II
Mortgage Loans on Real Estate
Maturity date	Dec. 30, 2025
Notes payable, gross	$ 252,544
Mortgages \| Secured loan \| Rego Park II \| LIBOR
Mortgage Loans on Real Estate
Basis spread over LIBOR	1.35%
Mortgages \| Secured loan \| 731 Lexington Avenue \| Retail space
Mortgage Loans on Real Estate
Maturity date	Aug. 05, 2022
Interest rate	3.78%
Notes payable, gross	$ 350,000		350,000
Mortgages \| Secured loan \| 731 Lexington Avenue \| Retail space \| LIBOR
Mortgage Loans on Real Estate
Basis spread over LIBOR	1.40%
Mortgages \| Secured loan \| 731 Lexington Avenue \| Office space
Mortgage Loans on Real Estate
Maturity date	Jun. 11, 2024
Interest rate	3.36%
Notes payable, gross	$ 500,000		$ 500,000
Mortgages \| Secured loan \| 731 Lexington Avenue \| Office space \| LIBOR
Mortgage Loans on Real Estate
Basis spread over LIBOR	0.90%