Share-based Compensation and Non-Qualified Deferred Compensation Plan (Summary Of Share Options Outstanding And Exercisable) (Details) - Jun. 30, 2015 - USD ($) $ / shares in Units, $ in Millions		Total
Outstanding and Exercisable Options, Number	[1]	295,205
Aggregate intrinsic value of outstanding options		$ 9.4
Aggregate Intrinsic Value of Exercisable Options		$ 9.4
Closing share price per share for calculation of aggregate intrinsic values		$ 74.28
Options outstanding at December 31, 2014, Weighted Average Exercise/Grant Price		38.97
Exercise Price Thirty Point Zero Six Member [Domain]
Range of exercise prices, minimum		30.06
Range of exercise prices, maximum		$ 30.06
Outstanding and Exercisable Options, Number	[1]	105,015
Outstanding and Exercisable Options, Weighted Average Price	[1]	$ 30.06
Range Of Exercise Prices Forty One Point Sixteen To Forty Three Point Ninety Four [Domain]
Range of exercise prices, minimum		41.16
Range of exercise prices, maximum		$ 43.94
Outstanding and Exercisable Options, Number	[1]	119,242
Outstanding and Exercisable Options, Weighted Average Price	[1]	$ 42.46
Range Of Exercise Prices Forty Eight Point Zero Two To Seventy Five Point Seventeen Member [Domain] [Domain]
Range of exercise prices, minimum		48.02
Range of exercise prices, maximum		$ 75.17
Outstanding and Exercisable Options, Number	[1]	70,948
Outstanding and Exercisable Options, Weighted Average Price	[1]	$ 60.92

[1] The aggregate intrinsic value of options outstanding and exercisable at June 30, 2015 was $9.4 million. The aggregate intrinsic value was calculated as the excess, if any, between our closing share price of $74.28 per share on June 30, 2015 and the strike price of the underlying award.