Employee Benefit Plans (Details 3) (Postretirement Benefits Other than Pensions, USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014
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	$ 678
Effect of a 1 percentage-point decrease in total of service and interest cost	(308)
Effect 1 percentage-point increase in postretirement benefit obligation	6,098
Effect of a 1 percentage-point decrease in postretirement benefit obligation	(4,893)
Estimated future benefit payments
2015	1,274
2016	1,333
2017	1,477
2018	1,623
2019	1,820
Years 2020 - 2024	$ 11,329

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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.

+ 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=35743120&loc=d3e1928-114920

+ Details

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- Definition

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.

+ References

+ Details

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- Definition

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

+ Details

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- Definition

The effect of a one-percentage-point increase 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.

+ References

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References