Property (Schedule Of Property) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Real Estate [Abstract]
Land	$ 944,272	$ 911,521
Land held for development	40,986	40,667
Land under development	29,495	53,076
Buildings and improvements	2,999,500	2,898,867
Construction in-progress	191,725	241,118
Total	$ 4,205,978	$ 4,145,249