Retirement Plans - Expected future benefit payments of US plan (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
2014	$ 1,254
2015	1,295
2016	1,370
2017	1,429
2018	1,502
2019 - 2023	11,347
US Plan
Defined Benefit Plan Disclosure [Line Items]
2014	825
2015	870
2016	945
2017	1,008
2018	1,078
2019 - 2023	8,519
Benefits equalization plan
Defined Benefit Plan Disclosure [Line Items]
2014	429
2015	425
2016	425
2017	421
2018	424
2019 - 2023	$ 2,828

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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=28361610&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

+ Details

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- Definition

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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- Definition

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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- Definition

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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