Share-Based Payments (Details 1) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Summary of share based compensation expense associated with different programs
Subtotal	$ 59.5	$ 48.5
Share-based compensation expense included in total costs and expenses	57.2	47.3
Capitalized share-based compensation costs	(2.3)	(1.2)
Stock Options [Member]
Summary of share based compensation expense associated with different programs
Share-based compensation expense	0.3	0.1
Market stock units [Member]
Summary of share based compensation expense associated with different programs
Share-based compensation expense	8.5	6.0
Time-vested restricted stock units [Member]
Summary of share based compensation expense associated with different programs
Share-based compensation expense	27.1	25.8
Performance-vested restricted stock units settled in shares [Member]
Summary of share based compensation expense associated with different programs
Share-based compensation expense	0	0.1
Cash settled performance shares [Member]
Summary of share based compensation expense associated with different programs
Share-based compensation expense	20.4	14.8
Employee stock purchase plan [Member]
Summary of share based compensation expense associated with different programs
Share-based compensation expense	$ 3.2	$ 1.7