Share-Based Payments (Details 1) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Summary of share based compensation expense associated with different programs
Subtotal	$ 60.6	$ 45.7	$ 189.1	$ 137.3
Capitalized share-based compensation costs	(2.4)	(1.5)	(7.4)	(4.0)
Share-based compensation expense included in total costs and expenses	58.2	44.2	181.7	133.3
Stock Options [Member]
Summary of share based compensation expense associated with different programs
Share-based compensation expense	0.1	0.7	0.5	1.6
Market stock units [Member]
Summary of share based compensation expense associated with different programs
Share-based compensation expense	12.2	5.6	27.2	17.2
Time-vested restricted stock units [Member]
Summary of share based compensation expense associated with different programs
Share-based compensation expense	25.3	21.4	77.2	69.5
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	20.6	16.4	76.8	45.1
Employee stock purchase plan [Member]
Summary of share based compensation expense associated with different programs
Share-based compensation expense	$ 2.4	$ 1.6	$ 7.4	$ 3.8