Investment in Unconsolidated Joint Ventures (Summary Of Financial Information For Joint Ventures) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Equity Method Investments and Joint Ventures [Abstract]
Net Investment in Properties	$ 736,735		$ 741,228
Total Assets	925,439		922,694
Debt	456,870		457,141
Total Liabilities	546,389		549,997
Equity	379,050		372,697
Our investment in and share of equity in earnings of unconsolidated joint ventures	112,856		$ 106,402
Revenues	35,062	$ 33,608
Property Operating Expense	(10,391)	(10,583)
Net Operating Income	24,671	23,025
Net Income	11,286	9,000
Investment in and share of net income (loss)	$ 5,324	$ 4,078