Accumulated Other Comprehensive Income (Loss) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), beginning balance	$ (3,333.4)
Accumulated other comprehensive income (loss), Other comprehensive income before reclassifications	9.9
Accumulated other comprehensive income (loss), Amounts reclassified from accumulated other comprehensive income	36.6
Accumulated other comprehensive income (loss), Current period other comprehensive income	46.5
Accumulated other comprehensive income (loss), ending balance	(3,286.9)
Translation Adjustments, beginning balance	(676.8)
Translation Adjustments, Other comprehensive income before reclassifications	14.4
Translation Adjustments, Amounts reclassified from accumulated other comprehensive income
Translation Adjustments, Current period other comprehensive income	14.4
Translation Adjustments, ending balance	(662.4)
Postretirement Plans, beginning balance	(2,656.6)
Postretirement Plans, Other comprehensive income before reclassifications	(4.5)
Postretirement Plans, Amounts reclassified from accumulated other comprehensive income	36.6
Postretirement Plans, Current period other comprehensive income	32.1
Postretirement Plans, ending balance	$ (2,624.5)

Other Comprehensive Income, Reclassification Adjustments Net of Tax

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The total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

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Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans, attributable to parent entity.

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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for translation gain (loss) realized upon the sale or liquidation of an investment in a foreign entity and foreign currency hedges that are designated and qualified as hedging instruments for hedges of the foreign currency exposure of a net investment in a foreign operation.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax, before reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement benefit plans.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income (loss) for actuarial gain (loss) related to pension and other postretirement benefit plans.

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