Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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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

+ Details

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- Definition

Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64852052&loc=d3e1703-114919

+ Details

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- References

No definition available.

+ Details

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- Details

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Pension and Other Postretirement Benefits - Schedule of Net Funded Status of the Plans (Detail) £ in Thousands, $ in Thousands	Dec. 31, 2017 USD ($)	Dec. 31, 2017 GBP (£)	Dec. 31, 2016 USD ($)	Dec. 31, 2016 GBP (£)	Dec. 31, 2015 USD ($)
Foreign Pension Benefits [Member]
Funded status of the plans:
Fair value of plan assets	$ 56,419	£ 41,820	$ 48,055	£ 38,955
Defined Benefit Pension Plan [Member] \| U.S. Defined Benefit Pension Plans [Member]
Funded status of the plans:
Fair value of plan assets	199,138		188,722
Defined Benefit Pension Plan [Member] \| U.S. Defined Benefit Pension Plans [Member] \| U.S. [Member]
Funded status of the plans:
Fair value of plan assets	199,138		188,722		$ 139,376
Less benefit obligations	254,976		244,440		181,803
Funded status at December 31	(55,838)		(55,718)
Defined Benefit Pension Plan [Member] \| Foreign Pension Benefits [Member]
Funded status of the plans:
Fair value of plan assets	56,419		48,055		49,628
Less benefit obligations	64,613		66,910		63,750
Funded status at December 31	(8,194)		(18,855)
Other Postretirement Benefit Plans [Member]
Funded status of the plans:
Fair value of plan assets	0		0		0
Less benefit obligations	16,979		19,059		$ 8,117
Funded status at December 31	$ (16,979)		$ (19,059)