Defined Benefit Plan, Excess Assets Transferred

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- Definition

Minimum service period required to be eligible for profit sharing contribution to the 401(k) plan.

+ References

No definition available.

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- Definition

Fair value assets with unobservable inputs reconciliation foreign currency effects

+ References

No definition available.

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- Definition

Fair value assets with unobservable inputs reconciliation gains and losses

+ References

No definition available.

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- Definition

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ 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 (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- References

No definition available.

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- References

No definition available.

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of purchases, (sales), issuances and (settlements) of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Amount of cost (reversal of cost) for pension and other postretirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(b)(4))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(b)(2))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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Retirement Benefit Plans Part 1 (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Contribution Plan [Abstract]
Total cost of benefits for U.S. and Non-U.S. Plans	$ 13,253	$ 12,108	$ 12,428
Maximum employer contribution to 401(k) Plan as a percentage of employee's compensation	3.00%
Minimum service period required to be eligible for profit sharing contribution to 401(k) plan (in years)	1
Expenses for 401(k) Plan	$ 4,404	8,359	8,098
Pension Plan \| Level 1
Fair Value of Plan Assets by Investment Type
Fair value of plan assets	6,305	19,858
Pension Plan \| Level 2
Fair Value of Plan Assets by Investment Type
Fair value of plan assets	0	26,531
Pension Plan \| Level 3
Fair Value of Plan Assets by Investment Type
Fair value of plan assets	11,163	9,562
Pension Plan \| Cash and Cash Equivalents \| Level 1
Fair Value of Plan Assets by Investment Type
Fair value of plan assets	6,305	663
Pension Plan \| Cash and Cash Equivalents \| Level 2
Fair Value of Plan Assets by Investment Type
Fair value of plan assets	0	0
Pension Plan \| Cash and Cash Equivalents \| Level 3
Fair Value of Plan Assets by Investment Type
Fair value of plan assets	0	0
Pension Plan \| Mutual Funds - U.S. Large-Cap \| Level 1
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		9,803
Pension Plan \| Mutual Funds - U.S. Large-Cap \| Level 2
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		0
Pension Plan \| Mutual Funds - U.S. Large-Cap \| Level 3
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		0
Pension Plan \| Mutual Funds - U.S. Small-Cap \| Level 1
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		2,584
Pension Plan \| Mutual Funds - U.S. Small-Cap \| Level 2
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		0
Pension Plan \| Mutual Funds - U.S. Small-Cap \| Level 3
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		0
Pension Plan \| Mutual Funds - International Equities \| Level 1
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		2,244
Pension Plan \| Mutual Funds - International Equities \| Level 2
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		0
Pension Plan \| Mutual Funds - International Equities \| Level 3
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		0
Pension Plan \| Mutual Funds - Fixed-Income Domestic \| Level 1
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		4,564
Pension Plan \| Mutual Funds - Fixed-Income Domestic \| Level 2
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		0
Pension Plan \| Mutual Funds - Fixed-Income Domestic \| Level 3
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		0
Pension Plan \| Collective Investment Funds [Member] \| Level 1
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		0
Pension Plan \| Collective Investment Funds [Member] \| Level 2
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		26,531
Pension Plan \| Collective Investment Funds [Member] \| Level 3
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		0
Pension Plan \| Investment Account held by Pension Plan \| Level 1
Fair Value of Plan Assets by Investment Type
Fair value of plan assets	0	0
Pension Plan \| Investment Account held by Pension Plan \| Level 2
Fair Value of Plan Assets by Investment Type
Fair value of plan assets	0	0
Pension Plan \| Investment Account held by Pension Plan \| Level 3
Fair Value of Plan Assets by Investment Type
Fair value of plan assets	11,163	9,562
Pension Plan \| Fair Value
Fair Value of Plan Assets by Investment Type
Fair value of plan assets	17,468	55,951
Pension Plan \| Fair Value \| Cash and Cash Equivalents
Fair Value of Plan Assets by Investment Type
Fair value of plan assets	6,305	663
Pension Plan \| Fair Value \| Mutual Funds - U.S. Large-Cap
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		9,803
Pension Plan \| Fair Value \| Mutual Funds - U.S. Small-Cap
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		2,584
Pension Plan \| Fair Value \| Mutual Funds - International Equities
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		2,244
Pension Plan \| Fair Value \| Mutual Funds - Fixed-Income Domestic
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		4,564
Pension Plan \| Fair Value \| Collective Investment Funds [Member]
Fair Value of Plan Assets by Investment Type
Fair value of plan assets		26,531
Pension Plan \| Fair Value \| Investment Account held by Pension Plan
Fair Value of Plan Assets by Investment Type
Fair value of plan assets	11,163	9,562
Foreign Plan \| Pension Plan
Defined Contribution Plan [Abstract]
Excess assets transferred	0	0
Fair Value of Plan Assets by Investment Type
Fair value of plan assets	11,163	9,562	10,691
Foreign Plan \| U.K. Pension Plan \| Pension Plan
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value at beginning of year	9,562	10,691
Purchases, sales, issuances and settlements, net	(535)	7
Net gain	1,190	674
Foreign currency	946	(1,810)
Fair value at end of year	$ 11,163	$ 9,562	$ 10,691