Postretirement Benefit Plans (Details 7) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
UNITED STATES [Member]
Estimated Future Benefit Payments
2013	$ 5,619
2014	6,331
2015	6,961
2016	7,445
2017	7,946
2018-2022	45,911
UNITED KINGDOM [Member]
Estimated Future Benefit Payments
2013	494
2014	500
2015	570
2016	611
2017	663
2018-2022	$ 3,675

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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

+ Details

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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.

+ References

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- Definition

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

+ References

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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.

+ References

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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.

+ References

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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.

+ References

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