Stock-Based Compensation (Summary Of Stock Options By Exercise Price Range) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011 years
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of shares, Outstanding	1,305
Outstanding, Average life	3.6
Outstanding, Average price	$ 72.08
Number of shares, Exercisable	1,106
Exercisable, Average price	$ 74.89
Under $57.34 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of shares, Outstanding	267
Outstanding, Average life	5.9
Outstanding, Average price	$ 46.40
Number of shares, Exercisable	127
Exercisable, Average price	$ 44.49
Exercise price range, Upper limit	$ 57.34
$57.88-$73.45 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of shares, Outstanding	342
Outstanding, Average life	1.2
Outstanding, Average price	$ 68.32
Number of shares, Exercisable	342
Exercisable, Average price	$ 68.32
Exercise price range, Lower limit	$ 57.88
Exercise price range, Upper limit	$ 73.45
$73.54-$81.90 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of shares, Outstanding	226
Outstanding, Average life	5.1
Outstanding, Average price	$ 76.59
Number of shares, Exercisable	173
Exercisable, Average price	$ 77.23
Exercise price range, Lower limit	$ 73.54
Exercise price range, Upper limit	$ 81.90
$82.50-$88.00 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of shares, Outstanding	193
Outstanding, Average life	3.3
Outstanding, Average price	$ 84.60
Number of shares, Exercisable	193
Exercisable, Average price	$ 84.60
Exercise price range, Lower limit	$ 82.50
Exercise price range, Upper limit	$ 88.00
$88.33-$88.33 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of shares, Outstanding	235
Outstanding, Average life	3.0
Outstanding, Average price	$ 88.33
Number of shares, Exercisable	234
Exercisable, Average price	$ 88.33
Exercise price range, Lower limit	$ 88.33
Exercise price range, Upper limit	$ 88.33
$89.46-$93.65 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of shares, Outstanding	42
Outstanding, Average life	4.7
Outstanding, Average price	$ 93.02
Number of shares, Exercisable	37
Exercisable, Average price	$ 92.93
Exercise price range, Lower limit	$ 89.46
Exercise price range, Upper limit	$ 93.65