Equity Incentive Plans (Summary Of Outstanding Options) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit	$ 45.20
Exercise price range, upper limit	$ 65.50
Options outstanding (in shares)	993,738	840,665
Weighted avg. life remaining (in years)	5 years 9 months
Weighted avg. exercise price	$ 42.74	$ 40.85
Aggregate intrinsic value	$ 11,680
$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
Weighted avg. life remaining (in years)	4 years 11 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
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)	16,060
Weighted avg. life remaining (in years)	5 years 9 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)	492,788
Weighted avg. life remaining (in years)	5 years 5 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)	189,678
Weighted avg. life remaining (in years)	9 years 5 months
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
Weighted avg. life remaining (in years)	2 years 9 months