Stock Based Compensation (Schedule Of Company's Outstanding Performance Share Units) (Details) - Performance Share Units	12 Months Ended
	Dec. 31, 2015 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Shares outstanding, Number of Shares, Beginning Balance	1,127,088
Grants, Number of Shares	355,688
Vests, Number of Shares	(458,755)
Performance adjustment, Number of Shares	70,140	[1]
Forfeitures, Number of Shares	(31,242)
Shares outstanding, Number of Shares, Ending Balance	1,062,919
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted-average grant-date fair value, shares outstanding, beginning balance (in dollars per share) | $ / shares	$ 49.63
Grants, weight-average grant-date fair value (in dollars per share) | $ / shares	61.82
Vests, weighted-average grant-date fair value (in dollars per share) | $ / shares	41.68	[1]
Forfeitures, weighted-average grant-date fair value (in dollars per share) | $ / shares	58.90
Weighted-average grant-date fair value, shares outstanding, ending balance (in dollars per share) | $ / shares	$ 56.37

[1] Represents the change in shares issued based upon the attainment of performance goals established by the Company.