Recent Transactions (Schedule Of Acquisition Cost Allocated To Net Assets Acquired) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2019 USD ($)
Business Acquisition [Line Items]
Land and leasehold interest	$ 103,532
Buildings and improvements and other assets	608,174
Above market lease values	487
In-place lease values	27,206
Sub Total	739,399
Less: Below market lease values	(2,480)
Net assets	736,919
99 Wood Avenue [Member]
Business Acquisition [Line Items]
Land and leasehold interest	9,261
Buildings and improvements and other assets	45,576
Above market lease values	431
In-place lease values	8,264
Sub Total	63,532
Less: Below market lease values	(1,674)
Net assets	$ 61,858
99 Wood Avenue [Member] | Above Market, In-Place And Below Market Leases [Member]
Business Acquisition [Line Items]
Amortization period	4 years 3 months 18 days
Soho Lofts Apartments [Member]
Business Acquisition [Line Items]
Land and leasehold interest	$ 27,601
Buildings and improvements and other assets	231,663
In-place lease values	5,480
Sub Total	264,744
Less: Below market lease values	(166)
Net assets	$ 264,578
Soho Lofts Apartments [Member] | In-Place And Below Market Leases [Member]
Business Acquisition [Line Items]
Amortization period	9 months 18 days
Liberty Towers [Member]
Business Acquisition [Line Items]
Land and leasehold interest	$ 66,670
Buildings and improvements and other assets	330,935
Above market lease values	56
In-place lease values	13,462
Sub Total	411,123
Less: Below market lease values	(640)
Net assets	$ 410,483
Liberty Towers [Member] | Above Market, In-Place And Below Market Leases [Member]
Business Acquisition [Line Items]
Amortization period	6 months