Employee Benefit Plan - Benefits Expected to be Paid Next Five Years (Details) $ in Thousands	Dec. 31, 2017 USD ($)
DB Pension Plan
Future Benefit Payments
2018	$ 3,947
2019	4,273
2020	4,155
2021	4,324
2022	4,227
2023-2027	23,444
Total	44,370
Life and Healthcare Plan
Future Benefit Payments
2018	502
2019	460
2020	446
2021	435
2022	435
2023-2027	2,262
Total	4,540
SERPs
Future Benefit Payments
2018	673
2019	668
2020	693
2021	684
2022	738
2023-2027	4,453
Total	$ 7,909

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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

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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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- Definition

Amount of benefits for defined benefit plan expected to be paid in remainder of 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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