Earnings Per Share (Components Of Earnings Per Common Share - Basic And Diluted) (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Continuing Operations:
Income from continuing operations	$ 32,918	$ 36,969	$ 72,842	$ 57,602
Gain on Sale of Property	46,953	32,224	155,998	47,987
Net income attributable to noncontrolling interests	(1,582)	(5,341)	(3,727)	(10,911)
Net income attributable to common shareholders - basic	78,289	63,852	225,113	94,678
Income attributable to operating partnership units	528	526	1,056	0
Net income attributable to common shareholders - diluted	$ 78,817	$ 64,378	$ 226,169	$ 94,678
Denominator:
Weighted average shares outstanding – basic (in shares)	127,505	127,788	127,714	127,700
Effect of dilutive securities:
Share options and awards (in shares)	813	848	799	894
Operating partnership units (in shares)	1,432	1,459	1,432	0
Weighted average shares outstanding – diluted (in shares)	129,750	130,095	129,945	128,594