Estimated Future Benefit Payments (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Pension Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
2013	$ 17,837
2014	18,361
2015	18,942
2016	19,486
2017	19,932
2018-2022	103,091
Other Postretirement Employee Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
2013	8,744
2014	8,947
2015	9,268
2016	9,190
2017	9,229
2018-2022	39,664
Expected Medicare Subsidy
Defined Benefit Plan Disclosure [Line Items]
2013	310
2014	313
2015	315
2016	313
2017	309
2018-2022	$ 1,436

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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

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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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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.

+ References

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