Retirement Plans (Details 6) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Total recognized in other comprehensive (loss) income	$ 31,911	$ (31,566)	$ 11,092
U.S. Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost			9
Interest cost	6,417	5,505	5,806
Expected return on plan assets	(9,060)	(8,034)	(7,619)
Net amortization: Net actuarial loss (gain)	2,216	3,432	3,009
Net periodic pension (benefit) cost	(427)	903	1,205
Net (loss) gain arising during the year	(19,965)	25,048	(2,042)
Amortization: Net loss (gain) recognized in net periodic pension cost	2,216	3,432	3,009
Total recognized in other comprehensive (loss) income	(17,749)	28,480	967
U.S. Retiree Healthcare Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	791	915	720
Interest cost	463	333	350
Expected return on plan assets	(435)	(355)	(287)
Net amortization: Prior service credit	(51)	(54)	(54)
Net amortization: Net actuarial loss (gain)	(35)
Net periodic pension (benefit) cost	733	839	729
Net (loss) gain arising during the year	(1,155)	1,629	(96)
Amortization: Prior service credit recognized in net periodic pension cost	(51)	(54)	(54)
Amortization: Net loss (gain) recognized in net periodic pension cost	(35)
Total recognized in other comprehensive (loss) income	(1,241)	1,575	(150)
Non-U.S. Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	4,579	4,467	3,752
Interest cost	2,195	1,966	1,988
Expected return on plan assets	(1,520)	(901)	(838)
Settlement loss	557
Net amortization: Prior service credit	(176)	(216)	(267)
Net amortization: Net actuarial loss (gain)	375	516	367
Net periodic pension (benefit) cost	6,010	5,832	5,002
Prior service cost	(796)	(232)
Net (loss) gain arising during the year	(15,168)	1,940	(5,622)
Amortization: Prior service credit recognized in net periodic pension cost	(176)	(216)	(267)
Amortization: Net loss (gain) recognized in net periodic pension cost	932	516	367
Other plans' impact on other comprehensive (loss) income			(5,970)
Foreign currency impact on defined benefit plan amounts recognized in other comprehensive (loss) income	2,287	(497)	(424)
Total recognized in other comprehensive (loss) income	$ (12,921)	$ 1,511	$ (11,916)

The amount of gains or losses recognized in net periodic benefit cost.

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The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

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An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

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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 total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

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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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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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Amount before tax of cost (credit) of benefit changes attributable to plan participants' prior service resulting from a plan amendment or plan initiation that has not been recognized in net periodic benefit cost (credit).

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Amount before tax of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) related to pension and other postretirement benefit plans.

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Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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Amount before tax of (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit.

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Amount before tax of reclassification adjustment from accumulated other comprehensive income (loss) for actuarial gain (loss) related to pension and other postretirement benefit plans.

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The amount of increase or decrease in other comprehensive income 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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Changes recognized in other comprehensive income for defined benefit plans, not otherwise separately disclosed in the financial statements.

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