Common Share Capitalization (Summary Of Common Shares Outstanding) (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Shares Outstanding, period begin	30,392,041	32,164,215	31,335,938	32,294,703
Shares repurchased	(242,161)	(51,518)	(1,186,058)	(182,006)
Director LTIP Units exercised	0	0	0	0
Common Shares Outstanding, period end	30,149,880	32,112,697	30,149,880	32,112,697