Stock Compensation Plans Stock Options (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding	12,787,545		13,528,862
Options Outstanding Weighted Average Exercise Price	$ 15.45		$ 14.75
Options granted	2,271,772
Options granted Weighted Average Exercise Price	$ 13.82
Options exercised	(2,616,422)
Options exercised Weighted Average Exercise Price	$ 10.28
Options expired	(36,720)
Options expired Weighted Average Exercise Price	$ 6.82
Options cancelled	(359,947)
Options cancelled Weighted Average Exercise Price	$ 17.29
Vested and expected to vest	12,273,772
Vested and expected to vest Weighted Average Exercise Price	$ 15.54
Exercisable	8,117,932
Exercisable Weighted Average Exercise Price	$ 16.62
Available for grant	11,126,549
Weighted Average Remaining Contractual Term (Years)	5 years 8 months
Vested and expected to vest Weighted Average Remaining Contractual Term (Years)	5 years 7 months
Exercisable Weighted Average Remaining Contractual Term (Years)	4 years 1 month
Options exercised Aggregate Intrinsic Value (in millions)	$ 23		$ 2		$ 10
Outstanding Aggregate Intrinsic Value (In millions)	113
Vested and expected to vest Intrinsic Value (in millions)	107
Exercisable Aggregate Intrinsic Value	$ 64
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit	$ 6.22
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit	$ 36.25
Weighted average fair value per share for the stock options	$ 6.28		$ 6.33		$ 6.94
Black-Scholes model assumptions:
Expected term (years)	6 years 3 months	[1]	6 years 3 months	[1]	6 years 3 months	[1]
Interest rate	1.11%	[1]	1.09%	[1]	2.28%	[1]
Volatility	46.70%	[1]	50.80%	[1]	49.50%	[1]
Dividend yield	0.00%	[1]	0.00%	[1]	0.00%	[1]
Grant Date February 28 2013 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding	1,942,818
Exercisable	10,366
Weighted Average Remaining Contractual Term (Years)	9 years 2 months
Exercise Price	$ 12.98
Grant Date February 27 2012 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding	1,591,837
Exercisable	379,677
Weighted Average Remaining Contractual Term (Years)	8 years 2 months
Exercise Price	$ 12.94
Grant Date February 22 2011 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding	1,168,252
Exercisable	561,034
Weighted Average Remaining Contractual Term (Years)	7 years 2 months
Exercise Price	$ 13.91
Grant Date February 23 2010 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding	1,016,731
Exercisable	733,248
Weighted Average Remaining Contractual Term (Years)	6 years 2 months
Exercise Price	$ 12.74
Grant Date February 26 2009 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding	1,140,723
Exercisable	1,140,723
Weighted Average Remaining Contractual Term (Years)	5 years 2 months
Exercise Price	$ 4.81
Grant Date February 21 2008 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding	1,065,835
Exercisable	1,065,835
Weighted Average Remaining Contractual Term (Years)	4 years 2 months
Exercise Price	$ 26.74
Grant Date February 27 2007 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding	1,197,897
Exercisable	1,197,897
Weighted Average Remaining Contractual Term (Years)	3 years 2 months
Exercise Price	$ 24.71
Grant Date December 6 2005 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding	632,947
Exercisable	632,947
Weighted Average Remaining Contractual Term (Years)	1 year 11 months
Exercise Price	$ 17.15
Grant Date December 9 2004 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding	997,368
Exercisable	997,368
Weighted Average Remaining Contractual Term (Years)	0 years 11 months
Exercise Price	$ 12.54
All Other Grant Dates [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding	2,033,137	[2]
Exercisable	1,398,837	[2]
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted Average Remaining Contractual Term (Years)	5 years 6 months
Exercise Price	$ 17.53
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted Average Remaining Contractual Term (Years)	4 years
Exercise Price	$ 18.43

[1] We review the assumptions used in our Black-Scholes model in conjunction with estimating the grant date fair value of the annual grants of stock-based awards by our Board of Directors.

[2] Options in the “All other” category had exercise prices ranging from $6.22 to $36.25. The weighted average exercise price for options outstanding and exercisable in that category was $17.53 and $18.43, respectively, while the remaining weighted average contractual term was 5.5 and 4.0 years, respectively.