Investment In Real Estate Joint Ventures And Partnerships (Schedule Of Combined Condensed Statements Of Operations) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Equity Method Investments [Line Items]
Revenues, net	$ 137,419	$ 138,316	$ 148,875
Expenses:
Depreciation and amortization	34,818	38,242	37,771
Interest, net	11,836	16,076	17,053
Operating	23,876	26,126	26,797
Real estate taxes, net	18,865	17,408	18,525
General and administrative	623	816	839
Provision for income taxes	112	113	197
Impairment loss	0	1,303	7,487
Total	90,130	100,084	108,669
Gain on sale of property	218,611	100,714	59,621
Net Income	59,781	53,421	45,377
Equity Method Investments [Member]
Expenses:
Gain on sale of non-operating property	0	373	0
Gain on sale of property	$ 12,492	$ 14,816	$ 5,171