INCOME TAXES - Tabular Reconciliation of Total Amounts of Unrecognized Tax Benefits (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Reconciliation Of Unrecognized Tax Benefits [Line Items]
Balance at January 1	$ 158.4	$ 168.0	$ 150.4
Increases related to prior periods	118.7	11.4	23.1
Decreases related to prior periods	(8.9)	(49.0)	(6.1)
Increases related to current period	19.1	34.4	23.7
Decreases related to settlements with taxing authorities	(0.6)	(4.8)	(14.1)
Decreases related to lapse of statute of limitations	(1.2)	(1.6)	(9.0)
Balance at December 31	285.5	158.4	168.0
Amounts impacting effective tax rate, if recognized balance at December 31	$ 159.0	$ 132.7	$ 112.2

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 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 total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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