Investment in Unconsolidated Joint Ventures (Summary Of Financial Information For Joint Ventures) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Equity Method Investments and Joint Ventures [Abstract]
Net Investment in Properties			$ 739,066		$ 758,582
Total Assets	$ 921,545		921,545		935,990
Debt	458,836		458,836		460,023
Total Liabilities	556,355		556,355		558,310
Equity	365,190		365,190		377,679
Our investment in and share of equity in earnings of unconsolidated joint ventures	105,819		105,819		$ 106,107
Revenues			100,649	$ 96,407
Property Operating Expense			(30,226)	(26,431)
Net Operating Income			70,423	69,976
Net Income			29,276	28,303
Investment in and share of net income (loss)	$ 4,152	$ 4,169	$ 12,362	$ 12,170