Equity Warrants (Details) (USD $) In Millions, except Share data	9 Months Ended	3 Months Ended	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2011 WarrantSettlement1 [Member]	Sep. 30, 2011 Warrant Settlement 2 [Member]
Warrants Settled		$ 3.4	$ 6.6
Class of Warrant or Right Average Exercise Price	$ 61.14	$ 59.79	$ 59.84
Shares Issued to Settle Warrants		37,959	706,395
Warrants Settled Cash		$ 153.7	$ 219.5