Common Stock (Antidilutive Securities Excluded From Computation Of Earnings Per Share) (Details) - shares		3 Months Ended		6 Months Ended		12 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Performance shares payout based upon performance		0	0	0	0	0	0
Performance shares payout level		100.00%	100.00%	100.00%	100.00%	100.00%	100.00%
Restricted Stock
Antidilutive Securities Excluded from the Computation of Diluted Earnings Per Share, Amount		55,368	58,792	63,793	68,409	65,432	62,352
Performance Shares
Antidilutive Securities Excluded from the Computation of Diluted Earnings Per Share, Amount	[1]	0	0	22,989	0	11,494	6,906

[1] Certain performance shares were excluded from the computation of diluted earnings per share as no payouts would have been required based upon performance at the end of each corresponding period.