Postretirement Benefits (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Service cost-benefits attributable to service during the period	$ 63us-gaap_DefinedBenefitPlanServiceCost	$ 82us-gaap_DefinedBenefitPlanServiceCost	$ 88us-gaap_DefinedBenefitPlanServiceCost
Interest cost on accumulated postretirement benefit obligation	136us-gaap_DefinedBenefitPlanInterestCost	118us-gaap_DefinedBenefitPlanInterestCost	120us-gaap_DefinedBenefitPlanInterestCost
Net amortization and deferral	35	46	51
Net periodic postretirement benefit cost	234	246	259
Net (gain) / loss during the year	377	(347)	(148)
Acquisition	0	60	0
Amortization of prior service cost and actuarial losses	(35)	(46)	(51)
Total recognized in comprehensive income	342	(333)	(199)
Total recognized in net periodic postretirement benefit cost and other comprehensive income	$ 576	$ (87)	$ 60

The total amount of net periodic benefit cost for defined benefit plans and other comprehensive income for the period.

No definition available.

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- Definition

Before tax amount of the income statement impact of the reclassification adjustment for amortization of prior service cost and actuarial losses.

+ References

No definition available.

+ Details

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- Definition

Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Gain or Loss

-URI http://asc.fasb.org/extlink&oid=6514294

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-SubTopic 60

-Glossary Gain or Loss

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- Definition

The amount of the transition obligation or asset recognized in net periodic benefit cost.

+ References

+ Details

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- Definition

The amount of increase in the benefit obligation attributed to business combinations.

+ References

+ Details

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- Definition

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

+ References

+ Details

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- Definition

The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

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- Definition

The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

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-Glossary Service Cost (Component of Net Periodic Pension Cost)

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- Definition

Amount before tax of reclassification adjustment from accumulated other comprehensive income (loss) for actuarial gain (loss) related to pension and other postretirement benefit plans.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

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