Other Financial Information, Other (Expense) Income, Net (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Other Financial Information [Abstract]
Interest income	$ 1.7	$ 2.9	$ 3.8	$ 5.7
Interest expense	(14.9)	(13.5)	(29.2)	(27.7)
Other	0.6	13.4	2.7	0.4
Other (expense) income, net	(12.6)	2.8	(22.7)	(21.6)
Privately-held investments, net gain		$ 14.8	$ 1.3	$ 0.8