Benefit Plans (Funded Status of Plan) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Benefit Plans [Abstract]
Projected benefit obligation	$ (6,925)	$ (6,695)	$ (6,583)
Accumulated benefit obligation	(6,925)	(6,695)
Fair value of plan assets	4,960	4,887	$ 4,851
Other liabilities	(1,965)	(1,808)
Funded status	(1,965)	(1,808)
Amounts recognized in accumulated other comprehensive loss consist of: Net loss	1,849	1,792
Total	$ 1,849	$ 1,792

Amount, after tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (i-k)
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580

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Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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- Definition

Amount, after tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

+ References

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans.

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