Pension and Employee Benefit Plans - Estimated future benefit payments expected to be paid (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Modified Retirement Plan \| Unfunded Plan
Defined Benefit Plan Disclosure [Line Items]
2019	$ 1,142
2020	1,227
2021	1,221
2022	1,214
2023	1,207
2024-2026	6,755
Total	12,766
Funded Plan \| Funded Plan
Defined Benefit Plan Disclosure [Line Items]
2019	1,083
2020	1,073
2021	1,056
2022	1,058
2023	1,037
2024-2026	4,984
Total	$ 10,291

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+ References

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

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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.

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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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