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Amount of the required periodic payments applied to principal.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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

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-Publisher FASB

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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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-Publisher FASB

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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 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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Other - Additional Information Domain (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended				3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Apr. 01, 2015	Apr. 01, 2014	Sep. 30, 2013 Minimum	Sep. 30, 2013 Maximum	Jun. 30, 2013 Northwind Holdings LLC [Member]	Jun. 30, 2013 Tailwind Holdings LLC [Member]
Debt Instrument, Periodic Payment, Principal									$ 30.0
Repayments of Long-term Debt			86.2	34.2						62.5
Gains (Losses) on Extinguishment of Debt										4.0
Unrecognized Tax Benefits	23.6		23.6
Unrecognized Tax Benefits That Would Not Effect Tax Rate	15.0		15.0
Unrecognized Tax Benefits, Increases Resulting from Prior Period Tax Positions	4.0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	0.1	(11.0)	0.2	(10.5)
2013 UK Tax rate	23.00%		23.00%
2014 UK Tax Rate						21.00%
2015 UK Tax Rate					20.00%
Income Tax Reconciliation, Change in Enacted Tax Rate							$ 4.0	$ 7.0