Stock-Based Compensation (Details 3) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Number of Shares Subject to Outstanding Options
Exercised (in shares)	(2,000)
Weighted-average exercise price of outstanding options
Exercised (in dollars per share)	$ 14.04
Performance Contingent
Number of shares outstanding subject to RSUs and vesting or performance conditions with vesting
Balance at the beginning of the period (in shares)	2,501	2,442	33
Granted (in shares)	510	447	2,483
Released RSUs and RSAs (in shares)	(452)	(388)	(74)
Forfeited (in shares)	(194)	0	0
Balance at the end of the period (in shares)	2,365	2,501	2,442
Weighted-average fair value per share at grant
Balance at the beginning of the period (in dollars per share)	$ 23.43	$ 24.62	$ 26.10
Granted (in dollars per share)	$ 23.25	$ 18.11	$ 24.61
Released RSUs and RSAs (in dollars per share)	$ 21.64	$ 24.77	$ 24.96
Forfeited (in dollars per share)	$ 24.37	$ 0.00	$ 0.00
Balance at the end of the period (in dollars per share)	$ 23.66	$ 23.43	$ 24.62
Stock options
Number of Shares Subject to Outstanding Options
Balance at the beginning of the period (in shares)	6,120	6,891	7,654
Granted (in shares)	820	335	629
Exercised (in shares)	(1,977)	(947)	(1,265)
Forfeited (in shares)	(139)	(159)	(127)
Balance at the end of the period (in shares)	4,824	6,120	6,891
Weighted-average exercise price of outstanding options
Balance at the beginning of the period (in dollars per share)	$ 20.30	$ 18.62	$ 16.91
Granted (in dollars per share)	$ 35.54	$ 21.91	$ 21.98
Exercised (in dollars per share)	$ 14.04	$ 7.98	$ 8.87
Forfeited (in dollars per share)	$ 25.69	$ 24.43	$ 29.15
Balance at the end of the period (in dollars per share)	$ 25.30	$ 20.30	$ 18.62
Additional disclosures
Aggregate intrinsic value of options outstanding	$ 51.2
Aggregate intrinsic value of options exercisable	45.3
Total intrinsic value of options exercised	41.4	15.2	17.1
Total estimated fair value of options vested	$ 3.7	$ 4.1	$ 6.4
Weighted-average assumptions
Risk-free interest rate, minimum (as a percent)	0.76%	0.74%	1.10%
Risk-free interest rate, maximum (as a percent)	2.02%	1.17%	2.57%
Volatility, minimum (as a percent)	58.00%	55.00%	49.00%
Volatility, maximum (as a percent)	60.00%	60.00%	55.00%
Dividend yield (as a percent)	0.00%	0.00%	0.00%
Weighted-average estimated fair value of awards granted (in dollars per share)	$ 19.96	$ 11.50	$ 11.11
Stock options | Minimum
Weighted-average assumptions
Expected life	5 years	5 years	5 years
Stock options | Maximum
Weighted-average assumptions
Expected life	6 years	6 years	6 years
RSUs
Number of shares outstanding subject to RSUs and vesting or performance conditions with vesting
Balance at the beginning of the period (in shares)	1,240	1,542	1,897
Granted (in shares)	572	528	471
Released RSUs and RSAs (in shares)	(630)	(752)	(797)
Forfeited (in shares)	(67)	(78)	(29)
Balance at the end of the period (in shares)	1,115	1,240	1,542
Weighted-average fair value per share at grant
Balance at the beginning of the period (in dollars per share)	$ 17.32	$ 15.47	$ 12.45
Granted (in dollars per share)	$ 23.47	$ 18.45	$ 24.96
Released RSUs and RSAs (in dollars per share)	$ 15.38	$ 14.19	$ 13.89
Forfeited (in dollars per share)	$ 18.14	$ 18.48	$ 15.35
Balance at the end of the period (in dollars per share)	$ 21.53	$ 17.32	$ 15.47
Employee Stock Purchase Plan
Weighted-average assumptions
Risk-free interest rate, minimum (as a percent)	0.09%	0.14%	0.05%
Risk-free interest rate, maximum (as a percent)	0.26%	0.29%	0.54%
Volatility, minimum (as a percent)	56.00%	51.00%	48.00%
Volatility, maximum (as a percent)	61.00%	64.00%	59.00%
Dividend yield (as a percent)	0.00%	0.00%	0.00%
Weighted-average estimated fair value of awards granted (in dollars per share)	$ 16.44	$ 8.07	$ 9.46
Employee Stock Purchase Plan | Minimum
Weighted-average assumptions
Expected life	6 months	6 months	6 months
Employee Stock Purchase Plan | Maximum
Weighted-average assumptions
Expected life	2 years	2 years	2 years