Pension and Other Postretirement Benefit Plans - Reconciliation of Change in Benefit Obligation and Change in Plan Assets (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
U.S. Pension
Change in benefit obligation:
Benefit obligation at beginning of period	$ 586.7	$ 656.3
Service cost	3.7	2.9	3.2
Interest cost	28.5	26.2	25.4
Amendments and settlements	0	0
Actuarial (gain) loss	119.8	(79.9)
Benefits paid	(20.9)	(18.8)
Special termination benefits	0	0
Translation adjustment	0	0
Benefit obligation at end of period	717.8	586.7	656.3
Change in plan assets:
Fair value of plan assets at beginning of period	503.5	417.6
Actual return on plan assets	34.2	79.1
Employer contributions	2.4	25.6
Benefits paid	(20.9)	(18.8)
Settlements	0	0
Translation adjustment	0	0
Fair value of plan assets at end of period	519.2	503.5	417.6
Funded status	(198.6)	(83.2)
Amounts recognized in the consolidated balance sheet:
Other long-term assets	0	0.3
Accrued liabilities	(2.5)	(2.3)
Other long-term liabilities	(196.1)	(81.2)
Foreign Pension
Change in benefit obligation:
Benefit obligation at beginning of period	459.5	509.2
Service cost	8.8	10.2	9.6
Interest cost	20.4	20.7	21.0
Amendments and settlements	0	(13.8)
Actuarial (gain) loss	66.5	(24.3)
Benefits paid	(22.4)	(22.8)
Special termination benefits	0	0.1
Translation adjustment	(39.8)	(19.8)
Benefit obligation at end of period	493.0	459.5	509.2
Change in plan assets:
Fair value of plan assets at beginning of period	417.0	390.6
Actual return on plan assets	40.7	57.6
Employer contributions	15.2	27.4
Benefits paid	(22.4)	(22.8)
Settlements	0	(13.8)
Translation adjustment	(35.4)	(22.0)
Fair value of plan assets at end of period	415.1	417.0	390.6
Funded status	(77.9)	(42.5)
Amounts recognized in the consolidated balance sheet:
Other long-term assets	45.5	62.7
Accrued liabilities	(3.0)	(3.5)
Other long-term liabilities	(120.4)	(101.7)
U.S. Other Postretirement
Change in benefit obligation:
Benefit obligation at beginning of period	91.6	102.0
Service cost	0.2	0.1	0.5
Interest cost	4.0	3.6	4.4
Amendments and settlements	0	0
Actuarial (gain) loss	(8.0)	(8.4)
Benefits paid	(4.5)	(5.7)
Special termination benefits	0	0
Translation adjustment	0	0
Benefit obligation at end of period	83.3	91.6	102.0
Change in plan assets:
Fair value of plan assets at beginning of period	0	0
Actual return on plan assets	0	0
Employer contributions	4.5	5.7
Benefits paid	(4.5)	(5.7)
Settlements	0	0
Translation adjustment	0	0
Fair value of plan assets at end of period	0	0	0
Funded status	(83.3)	(91.6)
Amounts recognized in the consolidated balance sheet:
Other long-term assets	0	0
Accrued liabilities	(5.1)	(6.9)
Other long-term liabilities	(78.2)	(84.7)
Foreign Other Postretirement
Change in benefit obligation:
Benefit obligation at beginning of period	42.4	73.8
Service cost	0.9	1.1	1.0
Interest cost	2.0	2.0	3.2
Amendments and settlements	0	(25.5)
Actuarial (gain) loss	6.9	(2.5)
Benefits paid	(2.6)	(2.4)
Special termination benefits	0.8	0.8
Translation adjustment	(3.6)	(4.9)
Benefit obligation at end of period	46.8	42.4	73.8
Change in plan assets:
Fair value of plan assets at beginning of period	0	0
Actual return on plan assets	0	0
Employer contributions	2.6	2.4
Benefits paid	(2.6)	(2.4)
Settlements	0	0
Translation adjustment	0	0
Fair value of plan assets at end of period	0	0	0
Funded status	(46.8)	(42.4)
Amounts recognized in the consolidated balance sheet:
Other long-term assets	0	0
Accrued liabilities	(2.0)	(2.3)
Other long-term liabilities	$ (44.8)	$ (40.1)

Defined Benefit Plan Plan Amendments and Settlements

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The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.

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Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan.

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The amount for overfunded plans recognized in the balance sheet as a noncurrent asset associated with a defined benefit pension plan or other postretirement defined benefit plan.

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

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The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

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The increase in the fair value of plan assets from contributions made by the employer.

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Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

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Amount of gain (loss) from foreign currency exchange rate changes for benefit obligation for plans of a foreign operation whose functional currency is not the reporting currency.

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The amount of increase or decrease in plan assets attributed to foreign currency changes. The effects of foreign currency exchange rate changes that are to be disclosed are those applicable to plans of a foreign operation whose functional currency is not the reporting currency.

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The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

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The amount that relates to an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include (a) making lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and (b) purchasing nonparticipating annuity contracts.

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The amount of increase related to special termination benefits offered to and accepted by employees in connection with their termination of employment that are only offered for a short period of time. A situation involving termination benefits may also involve a curtailment.

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For a classified balance sheet, the amount recognized in balance sheet as a current liability associated with an underfunded defined benefit plan.

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This represents the noncurrent liability for underfunded plans recognized in the balance sheet that is associated with the defined benefit pension plans and other postretirement defined benefit plans.

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