Employee Benefit Plans (Schedule of Expected Benefit Payments) (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Pension Plan [Member]
Year ending December 31, 2018	$ 1,539
Year ending December 31, 2019	1,711
Year ending December 31, 2020	1,764
Year ending December 31, 2021	1,867
Year ending December 31, 2022	1,910
Years ending December 31, 2023-2027	10,039
SERP [Member]
Year ending December 31, 2018	414
Year ending December 31, 2019	411
Year ending December 31, 2020	408
Year ending December 31, 2021	420
Year ending December 31, 2022	415
Years ending December 31, 2023-2027	$ 2,041

Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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