Reconciliation of Provision for Income Taxes (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of Provision of Income Taxes [Line Items]
United States statutory income tax provision	$ 50.9	$ 76.8	$ 88.9
Income and losses for which no provision or benefit has been recognized	35.7	13.5	7.0
Foreign rate differential and other foreign tax expense	(22.0)	(23.0)	(32.2)
Income tax withholdings	17.1	15.4	20.3
Permanent items	1.1	4.0	4.0
Enacted rate changes		8.9	9.0
Change in uncertain tax positions	0.2	4.4	4.5
Change in valuation allowances due to changes in judgment	7.0	(0.5)
Income tax credits, U.S.	(3.9)		(4.0)
Other	0.1	(0.2)	(0.2)
Provision for income taxes	$ 86.2us-gaap_IncomeTaxExpenseBenefit	$ 99.3us-gaap_IncomeTaxExpenseBenefit	$ 97.3us-gaap_IncomeTaxExpenseBenefit

Income Tax Reconciliation Income Tax Withholdings

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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