Retirement Benefit Plans (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Pension Plans
Defined Benefit Plans and Other Postretirement Benefit Plans
Plan contributions	$ 73		$ 252
U.S. Plans
Defined Benefit Plans and Other Postretirement Benefit Plans
Service cost	123	216	247	432
Interest cost	488	563	982	1,131
Expected return on plan assets	(672)	(910)	(1,342)	(1,820)
Amortization of net actuarial loss (gain)	30	1,073	74	1,096
Amortization of prior service cost (benefit)	10	(503)	21	46
Foreign currency	0	0	0	0
Net periodic (benefit) cost	(21)	439	(18)	885
Non-U.S. Plans
Defined Benefit Plans and Other Postretirement Benefit Plans
Service cost	38	33	76	66
Interest cost	134	121	266	243
Expected return on plan assets	(131)	(115)	(260)	(231)
Amortization of net actuarial loss (gain)	0	0	0	0
Amortization of prior service cost (benefit)	47	80	93	161
Foreign currency	(2)	(13)	16	29
Net periodic (benefit) cost	86	106	191	268
Postretirement Medical Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans
Plan contributions	278		542
Service cost	32	38	64	76
Interest cost	118	110	249	222
Expected return on plan assets	0	0	0	0
Amortization of net actuarial loss (gain)	(11)	127	0	101
Amortization of prior service cost (benefit)	(1)	(102)	(3)	(52)
Foreign currency	0	0	0	0
Net periodic (benefit) cost	$ 138	$ 173	$ 310	$ 347

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

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- Definition

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.

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512136

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Expected Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512171

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)(3)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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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.

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+ Details

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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.

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+ Details

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- Definition

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.

+ References

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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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)(1)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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

-URI http://asc.fasb.org/extlink&oid=6525008

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

+ Details

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