Income Taxes (Details) (USD $) In Millions	6 Months Ended
Jun. 30, 2011
Income Taxes
Balance at December 31, 2010	$ 157.1
Additions for tax positions of the current year	3.0
Additions for tax positions of the prior year	0.1
Reductions for tax positions of prior years	(9.5)
Settlements during the year	(1.7)
Balance at June 30, 2011	149.0
Amount of unrecognized tax benefit that will decrease within 12 months	$ 70.8

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

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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 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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The gross amount of increases 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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