Pension and Other Postretirement Benefits (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined benefit pension plans [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation, beginning balance	$ 453,722	$ 496,316
Service cost	4,546	6,181	6,530
Interest cost	22,026	20,112	21,624
Actuarial loss	68,634	(40,703)
Benefits paid	(27,365)	(28,060)
Transfers in	1,929	6,786
Curtailment gain	0	(8,715)
Plan Settlement	(4,949)	0
Special termination benefit	715	1,016	0
Participant contributions	906	545
Foreign exchange rate changes	(6,780)	244
Benefit obligation, ending balance	513,384	453,722	496,316
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning balance	453,578	387,553
Actual return on plan assets	26,785	80,979
Company contributions	7,621	5,984
Participant contributions	906	545
Benefits paid	(27,365)	(28,060)
Plan Settlements	(4,949)	0
Transfers in	1,929	6,627
Foreign exchange rate changes	(5,818)	(50)
Fair value of plan assets, ending balance	452,687	453,578	387,553
Funded/(underfunded) status, December 31	(60,697)	(144)
Defined benefit pension plans, U.S. [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation, beginning balance	374,740	423,547
Service cost	3,549	5,403
Interest cost	19,129	17,571
Actuarial loss	58,906	(40,734)
Benefits paid	(23,960)	(23,348)
Transfers in	0	0
Curtailment gain	0	(8,715)
Plan Settlement	0	0
Special termination benefit	715	1,016
Participant contributions	0	0
Foreign exchange rate changes	0	0
Benefit obligation, ending balance	433,079	374,740
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning balance	379,059	323,711
Actual return on plan assets	20,436	74,622
Company contributions	5,402	4,074
Participant contributions	0	0
Benefits paid	(23,960)	(23,348)
Plan Settlements	0	0
Transfers in	0	0
Foreign exchange rate changes	0	0
Fair value of plan assets, ending balance	380,937	379,059
Funded/(underfunded) status, December 31	(52,142)	4,319
Defined benefit pension plans, Non-U.S. [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation, beginning balance	78,982	72,769
Service cost	997	778
Interest cost	2,897	2,541
Actuarial loss	9,728	31
Benefits paid	(3,405)	(4,712)
Transfers in	1,929	6,786
Curtailment gain	0	0
Plan Settlement	(4,949)	0
Special termination benefit	0	0
Participant contributions	906	545
Foreign exchange rate changes	(6,780)	244
Benefit obligation, ending balance	80,305	78,982
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning balance	74,519	63,842
Actual return on plan assets	6,349	6,357
Company contributions	2,219	1,910
Participant contributions	906	545
Benefits paid	(3,405)	(4,712)
Plan Settlements	(4,949)	0
Transfers in	1,929	6,627
Foreign exchange rate changes	(5,818)	(50)
Fair value of plan assets, ending balance	71,750	74,519
Funded/(underfunded) status, December 31	(8,555)	(4,463)
Other postretirement benefit plans [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation, beginning balance	46,243	53,988
Service cost	139	233	273
Interest cost	2,179	2,061	2,532
Actuarial loss	3,049	(2,328)
Benefits paid	(7,568)	(9,133)
Curtailment gain	0	(1,675)
Special termination benefit	0	0	0
Participant contributions	2,833	3,039
Foreign exchange rate changes	(61)	58
Benefit obligation, ending balance	46,814	46,243	53,988
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning balance	0	0
Company contributions	4,735	6,094
Participant contributions	2,833	3,039
Benefits paid	(7,568)	(9,133)
Fair value of plan assets, ending balance	0	0	0
Funded/(underfunded) status, December 31	$ 46,814	$ 46,243

Defined Benefit Plan, Transfers In, Benefit Obligation

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Defined Benefit Plan, Transfers In, Plan Assets

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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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-Glossary Gain or Loss

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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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-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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-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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The amount of decrease that is related to an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services.

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-Glossary Plan Curtailment

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

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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 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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