Income Taxes (Details 3) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Summary of unrecognized tax benefits for the years ended
Beginning balance, January 1	$ 87.2	$ 77.8
Tax positions related to the current year Additions	20.6	1.3
Tax positions related to prior years Addtiions	7.0	13.7
Tax positions related to prior years Reductions	(1.7)	(5.6)
Lapses in statutes of limitations	(0.5)	0
Ending balance, December 31	$ 112.6	$ 87.2

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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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The gross amount of decreases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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The gross amount of increases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns.

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