Pensions and Other Post-retirement Benefits (Details 7) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Pension Benefits [Member]
Estimated Future Benefits payments
2013	$ 9,025
2014	9,375
2015	9,661
2016	10,344
2017	13,507
2018 through 2022	71,056
Other Benefits [Member]
Estimated Future Benefits payments
2013	2,663
2014	2,700
2015	2,743
2016	2,755
2017	2,815
2018 through 2022	13,597
Net of medicare part D Subsidy [Member]
Estimated Future Benefits payments
2013	2,287
2014	2,302
2015	2,320
2016	2,309
2017	2,343
2018 through 2022	$ 10,720

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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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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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