Income Taxes (Unrecognized Tax Benefits) (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2012
Balance at December 31, 2011	$ 76.4
Additions for tax positions of the current year	9.5
Additions for tax positions of the prior year	0.5
Reductions for tax positions of prior years	(25.3)
Settlements during the year	(5.4)
Lapses of applicable statutes of limitations	(0.3)
Balance at September 30, 2012	$ 55.4

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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