Employee Benefits - Changes in Postretirement Benefit Obligation and Plan Assets (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at end of year	$ 501,801	$ 448,851
U.S. Pension Plans [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	544,602	573,706
Service cost for benefits earned	3,057	3,644	3,121
Interest cost on projected benefit obligation	25,090	23,284	24,314
Actuarial (gain) loss	79,855	(29,875)
Plan amendments	216	0
Adjustments for expense/tax contained in service cost	0	0
Plan participants’ contributions	0	0
Benefits paid	(27,341)	(26,157)
Curtailments / settlements	0	0
Translation adjustments	0	0
Acquisitions/Transferred Liabilities	0	0
Benefit obligation at end of year	625,479	544,602	573,706
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	448,851	405,289
Actual return on plan assets	56,584	36,199
Employer contributions	23,707	33,520
Benefits paid	(27,341)	(26,157)
Settlements	0	0
Translation adjustments	0	0
Acquisitions/Transferred Liabilities	0	0
Fair value of plan assets at end of year	501,801	448,851	405,289
Funded status at end of year	(123,678)	(95,751)
Non-U.S. Pension Plans [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	818,578	780,164
Service cost for benefits earned	14,142	16,423	12,585
Interest cost on projected benefit obligation	33,360	31,103	30,944
Actuarial (gain) loss	236,096	2,655
Plan amendments	(10,814)	(873)
Adjustments for expense/tax contained in service cost	(2,087)	(2,343)
Plan participants’ contributions	2,096	2,793
Benefits paid	(32,134)	(27,571)
Curtailments / settlements	(9,270)	(768)
Translation adjustments	(86,413)	16,995
Acquisitions/Transferred Liabilities	1,712	0
Benefit obligation at end of year	965,266	818,578	780,164
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	799,670	776,188
Actual return on plan assets	135,947	11,970
Employer contributions	20,282	19,377
Benefits paid	(32,134)	(27,571)
Settlements	0	(768)
Translation adjustments	(74,680)	17,681
Acquisitions/Transferred Liabilities	1,712	0
Fair value of plan assets at end of year	852,893	799,670	776,188
Funded status at end of year	(112,373)	(18,908)
Postretirement Benefit Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	105,521	119,308
Service cost for benefits earned	1,295	1,526	1,357
Interest cost on projected benefit obligation	4,896	4,503	5,656
Actuarial (gain) loss	7,706	(15,524)
Plan amendments	0	0
Adjustments for expense/tax contained in service cost	0	0
Plan participants’ contributions	1,024	1,022
Benefits paid	(6,945)	(5,314)
Curtailments / settlements	0	0
Translation adjustments	0	0
Acquisitions/Transferred Liabilities	0	0
Benefit obligation at end of year	113,497	105,521	119,308
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Benefits paid	(6,945)	(5,314)
Acquisitions/Transferred Liabilities	$ 0	$ 0

Defined benefit plan, adjustments for expense or tax contained in service cost

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- Definition

Defined Benefit Plan, Curtailments And Settlements, Benefit Obligation

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Actual Return on Plan Assets (Component of Net Periodic Postretirement Benefit Cost)

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-Name Accounting Standards Codification

-Topic 715

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-Section 50

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-Glossary Actual Return on Plan Assets (Component of Net Periodic Pension Cost)

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- Definition

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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Gain or Loss

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- Definition

Fair value of assets transferred into (out of) a defined benefit pension plan.

+ References

No definition available.

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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.

+ References

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-Publisher FASB

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Projected Benefit Obligation

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Postretirement Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6503904

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Postretirement Benefits

-URI http://asc.fasb.org/extlink&oid=6521376

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- Definition

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

+ References

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- Definition

The amount of contributions made by plan participants. This item represents a periodic increase to the plan obligation and an increase to plan assets.

+ References

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- Definition

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.

+ References

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- Definition

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.

+ References

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- Definition

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.

+ References

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- Definition

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.

+ References

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- Definition

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.

+ References

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- Definition

The amount of increase or decrease due to a change in the terms of an existing plan or the initiation of a new plan. A plan amendment may increase or decrease benefits, including those attributed to years of service already rendered.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Plan Amendment

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Amount of net gain (loss) recognized in net periodic benefit cost as a result of 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, but are not limited to, lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contracts to cover vested benefits.

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- Definition

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.

+ References

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-Glossary Service Cost (Component of Net Periodic Pension Cost)

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