Shareholders' Equity (Schedule Of Share-Based Incentive Plan Grant Activity) (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011 years
Shareholders' Equity [Abstract]
Number of shares, Outstanding, Shares, Beginning Balance	1,454,050
Granted, Shares	403,130
Exercised, Shares	(94,725)
Forfeited, Shares	(13,300)
Number of shares, Outstanding, Shares, Ending Balance	1,747,255
Number of shares, Exercisable, Shares	839,375
Number of shares, Outstanding, Wtd. Avg. Exercise Price, Beginning Balance	$ 43.50
Granted, Wtd. Avg. Exercise Price	$ 70.23
Exercised, Wtd. Avg. Exercise Price	$ 40.06
Forfeited, Wtd. Avg. Exercise Price	$ 57.55
Number of shares, Outstanding, Wtd. Avg. Exercise Price, Ending Balance	$ 49.94
Number of shares, Exercisable, Wtd. Avg. Exercise Price	$ 39.16
Number of shares, Outstanding, Wtd. Avg. Remaining Contractual Term (years), Ending Balance	6.2
Number of shares, Exercisable, Wtd. Avg. Remaining Contractual Term (years)	4.1
Number of shares, Outstanding, Aggregate Intrinsic Value, Ending Balance	$ 12.1
Number of shares, Exercisable, Aggregate Intrinsic Value	$ 9.9