RETIREMENT PLANS, ASSUMPTIONS USED (Details) - Qualified noncontributory defined benefit retirement plan	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Benefit obligation:
Discount rate	4.14%	4.34%	3.95%
Salary increase rate	2.00%	2.00%	2.00%
Net periodic pension cost:
Discount rate	4.34%	3.95%	4.95%
Salary increase rate	2.00%	2.00%	3.00%
Amortization period in years	1 year	1 year 11 months 23 days	3 years 11 months 12 days

Amortization period of retirement plan.

No definition available.

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- Definition

The interest rate used to adjust for the time value of money for the 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 (k)(1)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

+ Details

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- Definition

Expected rate of compensation increases (for pay-related plans).

+ 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 (k)(2)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

The interest rate used to adjust for the time value of money.

+ References

+ Details

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- Definition

Expected rate of compensation increases (for pay-related plans).

+ 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 (k)(2)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- References

No definition available.

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- References

No definition available.

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