Property (Schedule Of Property) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Real Estate [Abstract]
Land	$ 929,958	$ 821,614
Land held for development	95,524	103,349
Land under development	17,367	24,297
Buildings and improvements	3,152,215	3,061,616
Construction in-progress	67,895	65,218
Total	$ 4,262,959	$ 4,076,094