Employee Benefit Plans (Other Changes in Plan Assets and Benefit Obligations) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($)
Retirement Benefits [Abstract]
Current year actuarial loss	$ (1,812)
Amortization of actuarial loss	2,835
Total recognized in other comprehensive loss	1,023
Estimated portion of net actuarial loss in accumulated other comprehensive loss	$ 2,700

No definition available.

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Amount, before tax, after reclassification adjustment, of increase (decrease) in accumulated other comprehensive income from gain (loss) of defined benefit plan.

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

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-Publisher FASB
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Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position.

+ References

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Amount, before tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of 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
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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