Redeemable Noncontrolling Interests (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012		Mar. 31, 2011
Redeemable Noncontrolling Interest [Roll Forward]
Balance at beginning of period	$ 243.4		$ 291.2
Change in related noncontrolling interest balance	(3.9)		(11.2)
Changes in redemption value of redeemable noncontrolling interests
Additions	0		3.6
Redemptions and other	(13.0)		(7.4)
Redemption value adjustments	(2.8)	[1]	9.7	[1]
Balance at end of period	$ 223.7		$ 285.9

[1] Redeemable noncontrolling interests are reported at their estimated redemption value in each reporting period, but not less than their initial fair value. Any adjustment to the redemption value impacts retained earnings or additional paid-in capital, except adjustments as a result of currency translation.