Summarized Information on Changes in Plan Obligations and Plan Assets (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Benefit obligation, beginning of year	$ 7,876
Benefit obligation at plan establishment		5,621
Service cost	1,081us-gaap_DefinedBenefitPlanServiceCost	994us-gaap_DefinedBenefitPlanServiceCost
Interest cost	163us-gaap_DefinedBenefitPlanInterestCost	105us-gaap_DefinedBenefitPlanInterestCost
Plan participants' contributions	486	283
Actuarial loss (gain)	3,057	(192)
Employee vested funds brought to plan, net	2,183us-gaap_DefinedBenefitPlanBenefitsPaid	1,065us-gaap_DefinedBenefitPlanBenefitsPaid
Translation gain	(636)
Benefit obligation, end of year	14,210	7,876
Fair value of plan assets, beginning of year	5,998
Fair value of plan assets at plan establishment		3,853
Actual return on plan assets	130	77
Employer contributions	1,285	720
Plan participants' contributions	483	283
Employee vested funds brought to plan, net	2,183us-gaap_DefinedBenefitPlanBenefitsPaid	1,065us-gaap_DefinedBenefitPlanBenefitsPaid
Translation loss	(459)
Fair value of plan assets, end of year	9,620	5,998
Unfunded liability as of December 31, 2014	$ 4,590	$ 1,878

Defined Benefit Plan Contributions By Plan Participants To Plan Assets

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Defined Benefit Plan, Fair Value of Plan Asset

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Defined Benefit Plan, Unfunded Status Of Plan

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- Definition

Defined Benefits Plan, Benefit Obligation

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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.

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

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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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- 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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-Glossary Projected Benefit Obligation

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-Name Accounting Standards Codification

-Glossary Accumulated Postretirement Benefit Obligation

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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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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Postretirement Benefits

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

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

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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 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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