2010 UK Tax Rate

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- Definition

2011 New Tax rate

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No definition available.

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2012 UK Tax rate - new

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No definition available.

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2012 UK Tax rate - old

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No definition available.

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Ultimate UK Tax rate

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No definition available.

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Unrecognized Tax Benefits, Reasonably Possible Decreases Resulting From Settlements With Taxing Authorities

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No definition available.

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Carrying value as of the balance sheet date of the sum of short-term debt and current maturities of long-term debt and capital lease obligations, which are due within one year (or one business cycle if longer).

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Interest rate stated in the contractual debt agreement.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to changes in the income tax rates under enacted tax laws in the period.

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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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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This element represents the total of interest expense recognized for an underpayment of income taxes computed by applying the applicable statutory rate of interest to the difference between a tax position recognized for financial reporting purposes and the amount previously taken or expected to be taken in a tax return of the entity and the amount of statutory penalties in the period in which the entity claims or expects to claim a tax position, in its tax return, that does not meet the minimum statutory threshold to avoid payment of penalties.

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The net amount of all increases and decreases in unrecognized tax benefits for the period.

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Other Other - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
2010 UK Tax Rate					27.00%
2011 New UK Tax rate					26.00%
Short-term Debt	$ 458.3		$ 458.3		$ 312.3
Repayments of Long-term Debt			45.6	66.9
Unrecognized Tax Benefits	32.2		32.2
Unrecognized Tax Benefits, Period Increase (Decrease)	61.1
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	0.1	1.5	(10.5)	4.1
2012 UK Tax rate - old	25.00%		25.00%
2012 UK Tax rate - new	24.00%		24.00%
Ultimate UK Tax rate	23.00%		23.00%
Income Tax Reconciliation, Change in Enacted Tax Rate	9.3	6.8
Issuance of Debt [Member]
Long-term Debt	250.0		250.0
Unsecuredseniornotes5point75percentdue2042 [Member]
Debt Instrument, Interest Rate, Stated Percentage	5.75%		5.75%
Northwind Holdings LLC [Member]
Repayments of Long-term Debt			38.1
Tailwind Holdings LLC [Member]
Repayments of Long-term Debt			7.5
Minimum [Member]
Unrecognized Tax Benefits Reasonably Possible Decreases Resulting from Settlements with Taxing Authorities	17.2
Maximum [Member]
Unrecognized Tax Benefits Reasonably Possible Decreases Resulting from Settlements with Taxing Authorities	$ 22.0