Earnings Per Share (Schedule Of Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings Per Share [Abstract]
INCOME FROM CONTINUING OPERATIONS	$ 61,561	$ 59,137	$ 121,176	$ 117,029
Less: Preferred share dividends	(2,011)	(135)	(4,021)	(271)
Less: Income from continuing operations attributable to noncontrolling interests	(1,938)	(1,660)	(3,622)	(3,432)
Less: Earnings allocated to unvested shares	(255)	(251)	(508)	(468)
Income from continuing operations available for common shareholders	57,357	57,091	113,025	112,858
Gain on sale of real estate, net	3,972	18,814	7,288	18,884
Net income available for common shareholders, basic and diluted	$ 61,329	$ 75,905	$ 120,313	$ 131,742
Weighted average common shares outstanding—basic	72,990	72,001	72,948	71,928
Stock options	35	123	49	133
Weighted average common shares outstanding—diluted	73,025	72,124	72,997	72,061
Earnings per common share, basic	$ 0.84	$ 1.05	$ 1.65	$ 1.83
Earnings per common share, diluted	$ 0.84	$ 1.05	$ 1.65	$ 1.83
Income from continuing operations attributable to the Trust	$ 59,623	$ 57,477	$ 117,554	$ 113,597