EMPLOYEE BENEFIT PLANS - Estimated Future Benefit Payments (Details) - Qualified Pension Plan $ in Thousands	Dec. 31, 2018 USD ($)
Qualified Plan
Estimated future benefit payments under defined benefit pension plan
2019	$ 19,544
2020	20,723
2021	21,153
2022	22,538
2023	22,765
2024 - 2028	120,355
Nonqualified Plan
Estimated future benefit payments under defined benefit pension plan
2019	6,788
2020	5,196
2021	5,286
2022	5,583
2023	4,754
2024 - 2028	$ 19,586

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108410482&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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