Employee Benefit Plans (Details 3) (Postretirement Benefits Other than Pensions, USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Postretirement Benefits Other than Pensions
Effect of a one-percentage-point change in assumed health care cost trend rates
Effect of a 1 percentage-point increase in total of service and interest cost	$ 588
Effect of a 1 percentage-point decrease in total of service and interest cost	(470)
Effect 1 percentage-point increase in postretirement benefit obligation	6,451
Effect of a 1 percentage-point decrease in postretirement benefit obligation	5,241
Estimated benefit payments
2013	1,330
2014	1,465
2015	1,568
2016	1,665
2017	1,772
Years 2018-2022	$ 11,372

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Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

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The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ 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 (m)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph m

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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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.

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

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