Retirement Plans (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
U.S. Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation, beginning balance	$ 134,593	$ 145,047
Interest cost	6,417	5,505	5,806
Actuarial losses (gains)	18,270	(13,328)
Benefits paid	(3,587)	(2,631)
Projected benefit obligation, ending balance	155,693	134,593	145,047
U.S. Retiree Healthcare Plan
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation, beginning balance	11,020	10,788
Service cost, including contributions by plan participants	1,623	1,733
Interest cost	463	333	350
Actuarial losses (gains)	1,253	(1,292)
Benefits paid	(847)	(542)
Projected benefit obligation, ending balance	13,512	11,020	10,788
Non-U.S. Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation, beginning balance	69,116	64,857
Service cost, including contributions by plan participants	5,171	5,079
Interest cost	2,195	1,966	1,988
Actuarial losses (gains)	17,967	(925)
Benefits paid	(1,195)	(1,743)
Plan amendments impact on projected benefit obligation	796	232
Plan obligation settlement	(2,766)
Other plans' impact on projected benefit obligation		227
Foreign currency impact on projected benefit obligation	(9,278)	(577)
Projected benefit obligation, ending balance	$ 82,006	$ 69,116	$ 64,857

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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Gain or Loss

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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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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

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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 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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Changes in the defined benefit obligation, not otherwise separately disclosed in the financial statements.

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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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The amount of decrease 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 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. Also includes contributions by plan participants, where applicable (primarily US Retiree Healtcare Plan).

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