Fair Value Unobservable Inputs (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Mandatorily redeemable noncontrolling interests
Fair value assets and liabilities measured on recurring basis unobservable input reconciliation
Balance at beginning of period, mandatorily redeemable noncontrolling interests	$ 52.0	$ 47.8
Level 3 additions	28.1	2.7
Level 3 reductions	(28.0)	(2.9)
Realized losses included in net income	(6.7)	(4.4)
Foreign currency translation	0.1	0
Balance at end of period, mandatorily redeemable noncontrolling interests	58.9	52.0
Level 3 additions	28.1	2.7
Level 3 reductions	(28.0)	(2.9)
Realized losses included in net income	(6.7)	(4.4)
Foreign currency translation	0.1	0
Foreign currency derivatives
Fair value assets and liabilities measured on recurring basis unobservable input reconciliation
Foreign currency translation		0
Foreign currency translation		0
Balance at beginning of period foreign currency derivatives		0.6
Level 3 additions		0
Level 3 reductions		0
Realized losses included in net income		(0.6)
Balance at end of period foreign currency derivatives		0
Level 3 additions		0
Level 3 reductions		0
Realized losses included in net income		$ (0.6)