Employee Benefit Plans (Schedule of Expected Benefit Payments) (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Other Benefits Plan [Member]
2018	$ 2,639
2019	2,653
2020	2,875
2021	2,971
2022	3,360
2023-2027	23,789
Totals	38,287
Pension Benefit Plan [Member]
2018	1,174
2019	1,414
2020	1,614
2021	1,816
2022	2,027
2023-2027	11,674
Totals	$ 19,719

Total amount of benefit payments.

No definition available.

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- Definition

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

+ 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 (f)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

+ Details

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- Definition

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.

+ References

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

+ References

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

+ References

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

+ References

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