Share-Based Compensation (Details) (USD $)	9 Months Ended		12 Months Ended	3 Months Ended	9 Months Ended
	Sep. 30, 2013 Plan	Sep. 30, 2012	Dec. 31, 2012	Sep. 30, 2013 Performance Units	Sep. 30, 2013 Performance Units	Sep. 30, 2013 Performance Units New Board Members	Sep. 30, 2013 Restricted Stock	Sep. 30, 2013 Employee Stock Option	Sep. 30, 2013 Performance Restricted Stock with Vesting Options	Sep. 30, 2013 Minimum	Sep. 30, 2013 Maximum	Sep. 30, 2013 March 2013 Grant Performance Units	Sep. 30, 2013 March 2013 Grant Performance Units Chief Executive Officer	Sep. 30, 2013 March 2013 Grant Performance Units Chief Financial Officer	Sep. 30, 2013 March 2013 Grant Performance Units Chief Operating Officer	Sep. 30, 2013 March 2013 Grant Performance Units Chief Accounting Officer	Sep. 30, 2013 March 2013 Grant Performance Units Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employee equity incentives plans	2
Shares awarded													186,858	93,429	62,286	28,029	21,800
Percentage vesting over three years												25.00%
Percentage vesting upon achievement of three-year Total Stockholder Return												25.00%
Percentage vesting upon achievement of total revenue												25.00%
Percentage vesting upon achievement of the three-year EBITDA												25.00%
Minimum operating revenue for vesting of awards												$ 12,000,000,000
Minimum EBITDA percentage for vesting of awards												2.50%
Unrecognized compensation expense							28,000,000	600,000
Weighted average period	1 year 8 months 18 days
Weighted-average period of unvested stock options to be recognized								2 years 3 months 18 days
Fair value of restricted and performance stock awards granted	33,300,000	23,000,000
Total fair value of restricted shares vested	$ 19,300,000	$ 24,300,000
Weighted-average grant date fair value per share of performance awards with vesting conditions					$ 30.80		$ 32.15		$ 28.24
Weighted-average grant date fair value per share	$ 33.02		$ 13.97			$ 14.67
Fair value assumptions, risk-free interest rate (in percent)					0.14%
Fair value assumptions, dividend yield (in percent)				0.00%
Fair value assumptions, expected term (in years)					9 months 29 days					6 years	7 years
Fair value assumptions, risk-free interest rates (in percent)										1.10%	1.40%
Fair value assumptions, expected volatilities (in percent)										41.30%	43.00%