Real Estate And Accumulated Depreciation (Changes In Accumulated Depreciation) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at beginning of year	$ 1,028,619	$ 1,058,040	$ 1,040,839
Additions at cost	120,426	125,226	130,698
Retirements or sales	(42,603)	(148,882)	(81,094)
Property held for sale	(18,800)	(5,765)	(32,403)
Balance at end of year	$ 1,087,642	$ 1,028,619	$ 1,058,040