Stock-Based Incentive Plan (Stock Option Activity) (Details) (USD $)	3 Months Ended
	Mar. 31, 2012
Stock-Based Incentive Plan [Abstract]
Outstanding at December 31, 2011, Number of Shares Under Option	23,599,256
Outstanding at December 31, 2011, Weighted Average Exercise Price per Share	$ 17.42
Options granted, Number of Shares Under Option	1,971,921
Options granted, Weighted Average Exercise Price per Share	$ 23.28
Options exercised, Number of Shares Under Option	(1,237,551)
Options exercised, Weighted Average Exercise Price per Share	$ 13.88
Options forfeited, Number of Shares Under Option	(194,352)
Options forfeited, Weighted Average Exercise Price per Share	$ 19.81
Outstanding at March 31, 2012, Number of Shares Under Option	24,139,274
Outstanding at March 31, 2012, Weighted Average Exercise Price per Share	$ 18.06
Vested and expected to vest at March 31, 2012, Number of Shares Under Option	23,065,876
Vested and expected to vest at March 31, 2012, Weighted Average Exercise Price per Share	$ 17.93
Options exercisable at March 31, 2012, Number of Shares Under Option	16,507,855
Options exercisable at March 31, 2012, Weighted Average Exercise Price per Share	$ 16.64