Common Share Capitalization (Summary Of Common Shares Outstanding) (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Shares Outstanding, period begin	32,112,697	32,743,356	32,294,703	33,126,012
Shares repurchased	(123,321)	(126,771)	(305,327)	(509,427)
Director LTIP Units exercised	2,801	2,475	2,801	2,475
Common Shares Outstanding, period end	31,992,177	32,619,060	31,992,177	32,619,060