Amounts Recognized on Consolidated Balance Sheets (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit cost (included in accrued liabilities)	$ (362.3)us-gaap_OtherAccruedLiabilitiesCurrent	$ (344.3)us-gaap_OtherAccruedLiabilitiesCurrent
Pension liabilities	(616.1)	(245.2)
Other postretirement benefits plan liabilities	(210.8)	(174.1)
Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Prepaid pension cost (included in other noncurrent assets)	14.4	8.0
Accrued benefit cost (included in accrued liabilities)	(8.7)	(8.2)
Pension liabilities	(616.1)	(245.2)
Other postretirement benefits plan liabilities
Net liabilities recognized in the Consolidated Balance Sheets	(610.4)	(245.4)
Other Postretirement Benefit Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Prepaid pension cost (included in other noncurrent assets)
Accrued benefit cost (included in accrued liabilities)	(1.2)	(1.4)
Pension liabilities
Other postretirement benefits plan liabilities	(210.8)	(174.1)
Net liabilities recognized in the Consolidated Balance Sheets	$ (212.0)	$ (175.5)

This represents the noncurrent liability recognized in the balance sheet that is associated with the defined benefit pension plans.

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The aggregate net amount recognized in the balance sheet associated with the defined benefit plan(s). Will normally be the same as the Defined Benefit Plan, Funded Status of Plan, Total.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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For a classified balance sheet, the carrying amount as of the balance sheet date of the portion of the obligations recognized for the various benefits provided to former or inactive employees, their beneficiaries, and covered dependents after employment but before retirement that is payable after one year (or beyond the operating cycle if longer).

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Cumulative employer's contributions in excess of net pension cost recognized, before the adoption of the recognition provisions of FAS 158. Under FAS 158, prepaid pension costs are no longer recognized in the statement of financial position. Note that there is a separate concept for noncurrent assets relating to defined benefit pension and other defined benefit postretirement plans for use under the recognition provisions of FAS 158.

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