Share-Based Compensation Share-Based Compensation Price Ranges (Details) (USD $)	12 Months Ended
	Dec. 31, 2012
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding Stock Options (in shares)	3,944,191
Outstanding Stock Options Weighted Average Remaining Contractual Term (in years)	5 years 1 month 27 days
Outstanding Stock Options Weighted Average Exercise Price (in dollars per share)	$ 26.33
Exercisable Stock Options (in shares)	2,090,468
Exercisable Stock Options, Weighted Average Exercise Price (in dollars per share)	$ 28.89
Exercise Price Range 0.00 to 17.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding Stock Options (in shares)	27,744
Outstanding Stock Options Weighted Average Remaining Contractual Term (in years)	1 month 13 days
Outstanding Stock Options Weighted Average Exercise Price (in dollars per share)	$ 11.98
Exercisable Stock Options (in shares)	27,744
Exercisable Stock Options, Weighted Average Exercise Price (in dollars per share)	$ 11.98
Exercise Price Range 18.00 to 23.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding Stock Options (in shares)	2,062,660
Outstanding Stock Options Weighted Average Remaining Contractual Term (in years)	5 years 3 months
Outstanding Stock Options Weighted Average Exercise Price (in dollars per share)	$ 20.11
Exercisable Stock Options (in shares)	885,433
Exercisable Stock Options, Weighted Average Exercise Price (in dollars per share)	$ 20.42
Exercise Price Range 24.00 to 29.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding Stock Options (in shares)	447,516
Outstanding Stock Options Weighted Average Remaining Contractual Term (in years)	7 years 7 months 13 days
Outstanding Stock Options Weighted Average Exercise Price (in dollars per share)	$ 24.69
Exercisable Stock Options (in shares)	48,516
Exercisable Stock Options, Weighted Average Exercise Price (in dollars per share)	$ 26.22
Exercise Price Range 30.00 to 47.30 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding Stock Options (in shares)	1,406,271
Outstanding Stock Options Weighted Average Remaining Contractual Term (in years)	4 years 4 months 9 days
Outstanding Stock Options Weighted Average Exercise Price (in dollars per share)	$ 36.27
Exercisable Stock Options (in shares)	1,128,775
Exercisable Stock Options, Weighted Average Exercise Price (in dollars per share)	$ 36.06