Share-Based Compensation (Schedule Of Performance Vesting Restricted Stock Units Granted) (Details)	9 Months Ended
	Sep. 30, 2018 shares
Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]
Grant year	2016
Three-year performance period ending December 31,	2018
Vesting shares, target (net of forfeited) (in shares)	77,250
Vesting shares, maximum (net of forfeited) (in shares)	144,844