Share-Based Payments (Details 1) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Summary of share based compensation expense associated with different programs
Subtotal	$ 69.1	$ 43.1	$ 128.6	$ 91.6
Share-based compensation expense included in total costs and expenses	66.4	41.8	123.6	89.1
Capitalized share-based compensation costs	(2.7)	(1.3)	(5.0)	(2.5)
Stock Options [Member]
Summary of share based compensation expense associated with different programs
Share-based compensation expense	0.1	0.8	0.4	0.9
Market stock units [Member]
Summary of share based compensation expense associated with different programs
Share-based compensation expense	6.6	5.6	15.1	11.6
Time-vested restricted stock units [Member]
Summary of share based compensation expense associated with different programs
Share-based compensation expense	24.8	22.2	51.9	48.1
Performance-vested restricted stock units settled in shares [Member]
Summary of share based compensation expense associated with different programs
Share-based compensation expense	0	0	0	0.1
Cash settled performance shares [Member]
Summary of share based compensation expense associated with different programs
Share-based compensation expense	35.8	13.9	56.2	28.7
Employee stock purchase plan [Member]
Summary of share based compensation expense associated with different programs
Share-based compensation expense	$ 1.8	$ 0.6	$ 5.0	$ 2.2