Income Taxes (Details 4) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Reconciliation of the beginning and ending amount of unrecognized tax benefits
Beginning Balance	$ 5.9	$ 1.0
Increases related to prior year tax positions	0.8
Decreases related to prior year tax positions	(5.8)	(0.7)
Increases related to current year tax positions	(0.1)	(5.7)
Settlements		(0.1)
Ending Balance	$ 1.0	$ 5.9

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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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-Name Accounting Standards Codification

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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 decreases in unrecognized tax benefits resulting from settlements with taxing authorities.

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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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