Expected Future Benefit Payments (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
UNITED KINGDOM
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2013	$ 549
2014	1,028
2015	817
2016	970
2017	1,239
2018-2022	7,138
Total	11,741
JAPAN
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2013	241
2014	152
2015	64
2016	70
2017	75
2018-2022	651
Total	$ 1,253

Defined Benefit Plan, Expected Future Benefit Payments, Total

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- Definition

Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit 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 (f)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

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- Definition

Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

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