Equity Incentive Plans (Summary Of Outstanding Options) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit	$ 46.86	$ 45.20	$ 45.20	$ 45.20
Exercise price range, upper limit	$ 65.50	$ 65.50	$ 65.50	$ 65.50
Options outstanding (in shares)	981,032		981,032		840,665
Weighted avg. life remaining (in years)			5 years 4 months
Weighted avg. exercise price	$ 42.69		$ 42.69		$ 40.85
Aggregate intrinsic value	$ 9,387		$ 9,387
$18.18 - 19.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit			$ 18.18
Exercise price range, upper limit			$ 19.99
Options outstanding (in shares)	201,859		201,859
Weighted avg. life remaining (in years)			4 years 5 months
20.00 - 29.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit			$ 20.00
Exercise price range, upper limit			$ 29.99
Options outstanding (in shares)	0		0
Weighted avg. life remaining (in years)			0 years
30.00 - 39.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit			$ 30.00
Exercise price range, upper limit			$ 39.99
Options outstanding (in shares)	14,774		14,774
Weighted avg. life remaining (in years)			5 years 5 months
40.00 - 49.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit			$ 40.00
Exercise price range, upper limit			$ 49.99
Options outstanding (in shares)	485,330		485,330
Weighted avg. life remaining (in years)			4 years 11 months
50.00 - 59.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit			$ 50.00
Exercise price range, upper limit			$ 59.99
Options outstanding (in shares)	185,716		185,716
Weighted avg. life remaining (in years)			9 years
60.00 - 65.50 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit			$ 60.00
Exercise price range, upper limit			$ 65.50
Options outstanding (in shares)	93,353		93,353
Weighted avg. life remaining (in years)			2 years 3 months
Share Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate			6.40%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate			50.30%	50.70%
Minimum [Member] | Share Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate				5.40%
Maximum [Member] | Share Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate				6.50%