Debt Instrument Extension Fee Percentage

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- Definition

Debt Instrument Extension Period

+ References

No definition available.

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- Definition

Debt Instrument, Number Of Extension Options

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No definition available.

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- Definition

Debt, Loans Payable, And Other Obligations, Net

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No definition available.

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- Definition

Libor Interest Rate

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No definition available.

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- Definition

Percentage Of Additional Interest Acquired

+ References

No definition available.

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- Definition

Secured Debt, Lending Institution

+ References

No definition available.

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- Definition

Secured Debt, Name of the Property

+ References

No definition available.

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- Definition

Unamortized Deferred Financing Costs

+ References

No definition available.

+ Details

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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

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount, after accumulated amortization, of debt discount.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with either short term or long term maturity that is uncollateralized (where debt is not backed by the pledge of collateral).

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- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Mortgages, Loans Payable And Other Obligations (Summary Of Mortgages, Loans Payable And Other Obligations) (Details)		3 Months Ended
	Jan. 31, 2019 USD ($)	Mar. 31, 2019 USD ($) item	Mar. 31, 2018 USD ($)	Jan. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)
Debt Instrument [Line Items]
Principal balance outstanding		$ 2,686,317,000			$ 2,792,651,000
Borrowings from revolving credit facility		92,000,000	$ 322,000,000
Payment for borrowings		204,000,000	$ 281,000,000
Secured Debt [Member]
Debt Instrument [Line Items]
Principal balance outstanding		1,536,346,000			1,440,396,000
Unamortized deferred financing costs		9,441,000			8,998,000
Total mortgages, loans payable and other obligations, net		$ 1,526,905,000			1,431,398,000
Secured Debt [Member] \| Park Square [Member]
Debt Instrument [Line Items]
Property Name		Park Square
Lender		Wells Fargo Bank N.A.
LIBOR		LIBOR+1.87
Spread over LIBOR		1.87%
Principal balance outstanding					25,167,000
Loan maturity date		Apr. 10, 2019
Secured Debt [Member] \| 250 Johnson Road [Member]
Debt Instrument [Line Items]
Property Name		250 Johnson
Lender		M&T Bank
LIBOR		LIBOR+2.35
Spread over LIBOR		2.35%
Principal balance outstanding		$ 42,000,000			41,769,000
Loan maturity date		May 20, 2019
Secured Debt [Member] \| 250 Johnson Road [Member] \| Construction Loan [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 42,000,000
Loan extension period		1 year
Extension fee		0.25%
Secured Debt [Member] \| Port Imperial 4/5 Hotel [Member]
Debt Instrument [Line Items]
Property Name		Port Imperial 4/5 Hotel
Lender		Fifth Third Bank & Santander
LIBOR		LIBOR+4.50
Spread over LIBOR		4.50%
Principal balance outstanding		$ 76,665,000			73,350,000
Loan maturity date		Oct. 06, 2019
Secured Debt [Member] \| Port Imperial 4/5 Hotel [Member] \| Construction Loan [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 94,000,000
Number of extension options \| item		2
Loan extension period		1 year
Extension fee		0.20%
Secured Debt [Member] \| Worcester [Member]
Debt Instrument [Line Items]
Property Name		Worcester
Lender		Citizens Bank
LIBOR		LIBOR+2.50
Spread over LIBOR		2.50%
Principal balance outstanding		$ 57,883,000			56,892,000
Loan maturity date		Dec. 10, 2019
Secured Debt [Member] \| Worcester [Member] \| Construction Loan [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 58,000,000
Number of extension options \| item		2
Loan extension period		1 year
Extension fee		0.15%
Secured Debt [Member] \| Monaco [Member]
Debt Instrument [Line Items]
Property Name		Monaco
Lender		The Northwestern Mutual Life Insurance Co.
Effective rate		3.15%
Principal balance outstanding		$ 167,966,000			168,370,000
Loan maturity date		Feb. 01, 2021
Adjustment for unamortized debt discount		$ 3,000,000
Secured Debt [Member] \| Port Imperial South 4/5 Retail [Member]
Debt Instrument [Line Items]
Property Name		Port Imperial South 4/5 Retail
Lender		American General Life & A/G PC
Effective rate		4.56%
Principal balance outstanding		$ 3,984,000			4,000,000
Loan maturity date		Dec. 01, 2021
Secured Debt [Member] \| Portside 7 [Member]
Debt Instrument [Line Items]
Property Name		Portside 7
Lender		CBRE Capital Markets/FreddieMac
Effective rate		3.57%
Principal balance outstanding		$ 58,998,000			58,998,000
Loan maturity date		Aug. 01, 2023
Secured Debt [Member] \| Alterra I & II [Member]
Debt Instrument [Line Items]
Property Name		Alterra I & II
Lender		Capital One/FreddieMac
Effective rate		3.85%
Principal balance outstanding		$ 100,000,000			100,000,000
Loan maturity date		Feb. 01, 2024
Secured Debt [Member] \| The Chase At Overlook Ridge [Member]
Debt Instrument [Line Items]
Property Name		The Chase at Overlook Ridge
Lender		New York Community Bank
Effective rate		3.74%
Principal balance outstanding		$ 135,750,000			135,750,000
Loan maturity date		Jan. 01, 2025
Secured Debt [Member] \| Portside 5/6 [Member]
Debt Instrument [Line Items]
Property Name		Portside 5/6
Lender		New York Life Insurance Company
Effective rate		4.56%
Principal balance outstanding		$ 97,000,000			97,000,000
Loan maturity date		Mar. 10, 2026
Secured Debt [Member] \| Marbella I [Member]
Debt Instrument [Line Items]
Property Name		Marbella
Lender		New York Life Insurance Company
Effective rate		4.17%
Principal balance outstanding		$ 131,000,000			131,000,000
Loan maturity date		Aug. 10, 2026
Secured Debt [Member] \| Marbella II [Member]
Debt Instrument [Line Items]
Property Name		Marbella II
Lender		New York Life Insurance Company
Effective rate		4.29%
Principal balance outstanding		$ 117,000,000
Loan maturity date		Aug. 10, 2026
Secured Debt [Member] \| 101 Hudson [Member]
Debt Instrument [Line Items]
Property Name		101 Hudson
Lender		Wells Fargo CMBS
Effective rate		3.20%
Principal balance outstanding		$ 250,000,000			250,000,000
Loan maturity date		Oct. 11, 2026
Secured Debt [Member] \| Short Hills Portfolio [Member]
Debt Instrument [Line Items]
Property Name		Short Hills Portfolio
Lender		Wells Fargo CMBS
Effective rate		4.15%
Principal balance outstanding		$ 124,500,000			124,500,000
Loan maturity date		Apr. 01, 2027
Secured Debt [Member] \| 150 Main St [Member]
Debt Instrument [Line Items]
Property Name		150 Main St.
Lender		Natixis Real Estate Capital LLC
Effective rate		4.48%
Principal balance outstanding		$ 41,000,000			41,000,000
Loan maturity date		Aug. 05, 2027
Secured Debt [Member] \| Port Imperial South 11 [Member]
Debt Instrument [Line Items]
Property Name		Port Imperial South 11
Lender		The Northwestern Mutual Life Insurance Co.
Effective rate		4.52%
Principal balance outstanding		$ 100,000,000			100,000,000
Loan maturity date		Jan. 10, 2029
Secured Debt [Member] \| Port Imperial 4/5 Garage Development [Member]
Debt Instrument [Line Items]
Property Name		Port Imperial South 4/5 Garage
Lender		American General Life & A/G PC
Effective rate		4.85%
Principal balance outstanding		$ 32,600,000			$ 32,600,000
Loan maturity date		Dec. 01, 2029
Unconsolidated Joint Venture Multi-Family Properties [Member] \| Marbella II [Member]
Debt Instrument [Line Items]
Percentage of additional interest acquired	50.00%
Mortgage loan	$ 117,000,000			$ 74,700,000