Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Loss [Abstract]
Net unrealized gains (losses) on securities	$ 154	$ (20)
Tax effect	(33)	7
Net of tax amount	121	(13)
Accumulated pension adjustment	(7,784)	(6,366)	$ (6,777)
Tax effect	1,635	2,164	2,304
Net of tax amount	(6,149)	(4,202)	$ (4,473)
Total accumulated other comprehensive loss	$ (6,028)	$ (4,215)

Accumulated Other Comprehensive Income Loss Available For Sale Securities Tax

No definition available.

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- Definition

Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Tax

+ References

No definition available.

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- Definition

Accumulated Other Comprehensive Income Unrealized Holding Gain Loss On Securities Before Tax

+ References

No definition available.

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- Definition

Accumulated appreciation or loss, net of tax, in value of the total of available-for-sale securities at the end of an accounting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Subparagraph (i-k)
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- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580

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- Definition

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

+ References

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