Stock-Based Compensation- Restricted Stock and Restricted Stock Units Activity (Details) (USD $)	9 Months Ended
	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested shares outstanding, Beginning balance	3,705,000
Granted	721,000
Forfeited	(399,000)
Vested	(1,118,000)
Non-vested shares outstanding, Ending balance	2,909,000
Non-vested shares outstanding, Weighted Average Grant Date Fair Value per Share, Beginning balance	$ 33.31
Granted, Weighted Average Grant Date Fair Value per Share	$ 25.24
Forfeited, Weighted Average Grant Date Fair Value per Share	$ 26.00
Vested, Weighted Average Grant Date Fair Value per Share	$ 36.61
Non-vested shares outstanding, Weighted Average Grant Date Fair Value per Share, Ending balance	$ 30.19
Service - Based Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested shares outstanding, Beginning balance	2,999,000
Granted	382,000
Forfeited	(353,000)
Vested	(1,088,000)
Non-vested shares outstanding, Ending balance	1,940,000
Performance Market Based Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested shares outstanding, Beginning balance	706,000
Granted	339,000
Forfeited	(46,000)
Vested	(30,000)
Non-vested shares outstanding, Ending balance	969,000