Share-Based Compensation (Details 2) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011 Y
Summary of information regarding the outstanding and exercisable stock options
Options Outstanding	13,570
Outstanding Options, Weighted-Average Remaining Contractual Life	7
Outstanding Options, Weighted Average Exercise Price Per Share	$ 61.68
Options Exercisable	8,841
Options Exercisable, Weighted Average Exercise Price Per Share	$ 57.37
Exercise Price Range 20.00-40.00 [Member]
Summary of information regarding the outstanding and exercisable stock options
Range of exercise prices, upper limit	$ 40.00
Range of exercise prices, lower limit	$ 20.00
Options Outstanding	1,098
Outstanding Options, Weighted-Average Remaining Contractual Life	3
Outstanding Options, Weighted Average Exercise Price Per Share	$ 27.52
Options Exercisable	1,098
Options Exercisable, Weighted Average Exercise Price Per Share	$ 27.52
Exercise Price Range 40.01-50.00 [Member]
Summary of information regarding the outstanding and exercisable stock options
Range of exercise prices, upper limit	$ 50.00
Range of exercise prices, lower limit	$ 40.01
Options Outstanding	1,520
Outstanding Options, Weighted-Average Remaining Contractual Life	4
Outstanding Options, Weighted Average Exercise Price Per Share	$ 49.25
Options Exercisable	1,520
Options Exercisable, Weighted Average Exercise Price Per Share	$ 49.25
Exercise Price Range 50.01-60.00 [Member]
Summary of information regarding the outstanding and exercisable stock options
Range of exercise prices, upper limit	$ 60.00
Range of exercise prices, lower limit	$ 50.01
Options Outstanding	4,304
Outstanding Options, Weighted-Average Remaining Contractual Life	6
Outstanding Options, Weighted Average Exercise Price Per Share	$ 55.17
Options Exercisable	3,348
Options Exercisable, Weighted Average Exercise Price Per Share	$ 54.77
Exercise Price Range 60.01-80.00 [Member]
Summary of information regarding the outstanding and exercisable stock options
Range of exercise prices, upper limit	$ 80.00
Range of exercise prices, lower limit	$ 60.01
Options Outstanding	2,584
Outstanding Options, Weighted-Average Remaining Contractual Life	8
Outstanding Options, Weighted Average Exercise Price Per Share	$ 60.57
Options Exercisable	839
Options Exercisable, Weighted Average Exercise Price Per Share	$ 60.63
Exercise Price Range 80.01-120.00 [Member]
Summary of information regarding the outstanding and exercisable stock options
Range of exercise prices, upper limit	$ 120.00
Range of exercise prices, lower limit	$ 80.01
Options Outstanding	4,064
Outstanding Options, Weighted-Average Remaining Contractual Life	8
Outstanding Options, Weighted Average Exercise Price Per Share	$ 83.18
Options Exercisable	2,036
Options Exercisable, Weighted Average Exercise Price Per Share	$ 82.48