Employee Benefit Plans, Share Based Compensation, Equity Instruments Other Than Options (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Employee Stock Purchase Plan 2008 [Member]
Employee Stock Purchase Plan
Incremental offering period as approved by the Board	6 months
Stock Issued During Period, Shares, Employee Stock Purchase Plans	1.9		1.7
Average Price of Common Stock, Per Share	$ 15.05		$ 17.79
Common Stock, Capital Shares Reserved for Future Issuance	19.0
Restricted Stock Units (RSUs) [Member]
Restricted Stock Units And Performance Share Awards Activities
Awards Granted, Number of Shares	7.7
Awards Vested, Number of Shares	(3.8)
Awards Canceled, Number of Shares	(0.7)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Awards Granted, Weighted Average Grant-Date Fair Value	$ 20.41
Awards Vested, Weighted Average Grant-Date Fair Value	$ 28.80
Awards Canceled, Weighted Average Grant-Date Fair Value	$ 24.20
Performance Shares [Member]
Restricted Stock Units And Performance Share Awards Activities
Awards Granted, Number of Shares	2.0	[1]
Awards Vested, Number of Shares	(1.0)
Awards Canceled, Number of Shares	(1.8)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Awards Granted, Weighted Average Grant-Date Fair Value	$ 21.36	[1]
Awards Vested, Weighted Average Grant-Date Fair Value	$ 28.26
Awards Canceled, Weighted Average Grant-Date Fair Value	$ 29.05
Aggregate Number Of Shares Subject to PSAs Granted	1.0
Minimum shares to be Issued on achievement of performance goals in respect of PSAs	0
Maximum shares to be issued on achievement of performance goals in respect of PSAs	2.0
RSA [Member]
Restricted Stock Units And Performance Share Awards Activities
Awards Vested, Number of Shares	(0.2)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Awards Vested, Weighted Average Grant-Date Fair Value	$ 19.59
RSUs, RSAs, and PSAs [Member]
Restricted Stock Units And Performance Share Awards Activities
Beginning Balance, Number of Shares	26.8
Ending Balance, Number of Shares	29.0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Beginning Balance, Weighted Average Grant-Date Fair Value	$ 27.76
Ending Balance, Weighted Average Grant-Date Fair Value	$ 25.28
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms	1 year 8 months 12 days
RSUs and PSAs, Aggregate Intrinsic Value at Period End	$ 538.4
Vested and Expected-to-Vest RSUs and PSAs, Number of Shares at Period End	24.9
Vested and Expected-to-Vest RSUs and PSAs, Weighted Average Grant-Date Fair Value at Period End	$ 23.95
Vested and Expected-to-Vest RSUs and PSAs, Weighted Average Remaining Contractual Term at Period End	1 year 7 months 6 days
Vested and Expected-to-Vest RSUs and PSAs, Aggregate Intrinsic Value at Period End	$ 461.3

[1] The number of shares subject to PSAs granted represents the aggregate maximum number of shares that may be issued pursuant to the award over its full term. The aggregate number of shares subject to these PSAs that would be issued if performance goals determined by the Compensation Committee are achieved at target is 1.0 million shares. Depending on achievement of such performance goals, the range of shares that could be issued under these awards is 0 to 2.0 million shares.