Share-Based Compensation Plans (Details 1) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012
Summary of stock option activity
Outstanding Ending Balance, Shares	3,148
Exercisable, Shares	2,032
Outstanding weighted average exercise price, Ending Balance	$ 46.36
Exercisable, weighted average exercise price	$ 45.76
Outstanding, weighted average remaining contractual term (years)	3 years 7 months 2 days
Stock options [Member]
Summary of stock option activity
Outstanding Beginning Balance, Shares	3,297
Granted, Shares	456
Exercised, Shares	(508)
Forfeited or expired, Shares	(97)
Vested or expected to vest, Shares	3,077
Outstanding, weighted average exercise price, Beginning Balance	$ 44.25
Granted, weighted average exercise price	$ 53.63
Exercised, weighted average exercise price	$ 38.68
Forfeited or expired, weighted average exercise price	$ 48.92
Vested or expected, weighted average exercise price	$ 46.31
Vested or expected to vest, weighted average remaining contractual term (years)	3 years 1 month 6 days
Exercisable, weighted average remaining contractual term (years)	2 years 7 months 6 days
Outstanding, Aggregate Intrinsic Value, of In-The-Money Options	$ 18,566
Vested or expected to vest, Aggregate Intrinsic Value of In-The-Money Options	18,313
Exercisable, Aggregate Intrinsic Value of In-The-Money Options	$ 14,106