Equity Incentive Plan Details 1 (Details) (USD $)	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award
Options, Outstanding, Number	2,394,938	2,673,566
Options, Outstanding, Weighted Average Exercise Price	$ 82.16	$ 73.24
Options, Outstanding, Weighted Average Remaining Contractual Term	5.7
Options, Exercisable, Number	1,520,653
$0.0-$40.0 Range of Exercise Price
Share-based Compensation Arrangement by Share-based Payment Award
Options, Outstanding, Number	306,337
Options, Outstanding, Weighted Average Exercise Price	$ 35.95
Options, Outstanding, Weighted Average Remaining Contractual Term	1.6
Options, Exercisable, Number	306,337
$40.0-$53.0 Range of Exercise Price
Share-based Compensation Arrangement by Share-based Payment Award
Options, Outstanding, Number	478,363
Options, Outstanding, Weighted Average Exercise Price	$ 49.66
Options, Outstanding, Weighted Average Remaining Contractual Term	3.4
Options, Exercisable, Number	478,363
$53.0-$74.0 Range of Exercise Price
Share-based Compensation Arrangement by Share-based Payment Award
Options, Outstanding, Number	571,300
Options, Outstanding, Weighted Average Exercise Price	$ 71.28
Options, Outstanding, Weighted Average Remaining Contractual Term	6.1
Options, Exercisable, Number	435,060
$74.0-$113.0 Range of Exercise Price
Share-based Compensation Arrangement by Share-based Payment Award
Options, Outstanding, Number	646,298
Options, Outstanding, Weighted Average Exercise Price	$ 101.84
Options, Outstanding, Weighted Average Remaining Contractual Term	6.7
Options, Exercisable, Number	259,488
$113.0-$137.0 Range of Exercise Price
Share-based Compensation Arrangement by Share-based Payment Award
Options, Outstanding, Number	202,475
Options, Outstanding, Weighted Average Exercise Price	$ 133.00
Options, Outstanding, Weighted Average Remaining Contractual Term	8.8
Options, Exercisable, Number	41,405
Greater than $137.0 Exercise Price
Share-based Compensation Arrangement by Share-based Payment Award
Options, Outstanding, Number	190,165
Options, Outstanding, Weighted Average Exercise Price	$ 149.95
Options, Outstanding, Weighted Average Remaining Contractual Term	9.8
Options, Exercisable, Number	0