Equity Incentive Plans (Summary Of Exercisable Options) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit	$ 45.20	$ 45.20	$ 45.20	$ 45.20
Exercise price range, upper limit	$ 65.50	$ 65.50	$ 65.50	$ 65.50
Options outstanding (in shares)	666,534		666,534
Weighted avg. life remaining (in years)			4 years 0 months
Weighted avg. exercise price	$ 39.48		$ 39.48
Aggregate intrinsic value	$ 11,752		$ 11,752
$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 7 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)	15,050		15,050
Weighted avg. life remaining (in years)			5 years 7 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)	344,397		344,397
Weighted avg. life remaining (in years)			4 years 0 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)	11,875		11,875
Weighted avg. life remaining (in years)			4 years 7 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		93,353
Weighted avg. life remaining (in years)			2 years 6 months