Retirement Plans and Other Postretirement Benefits - Summary of Benefit Payments Expected to be Paid (Details 4) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Retirement Plans [Member]
Summary of benefit payments expected to be paid
2013	$ 1,905
2014	1,955
2015	2,142
2016	2,268
2017	2,310
Years 2018-2022	11,068
Other Post Retirement Benefits [Member]
Summary of benefit payments expected to be paid
2013	82
2014	111
2015	122
2016	128
2017	135
Years 2018-2022	$ 750

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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

+ Details

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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

+ Details

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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.

+ References

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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

+ Details

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