RETIREMENT PLANS, ASSUMPTIONS USED (Details) (Nonqualified defined benefit retirement plan)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Nonqualified defined benefit retirement plan
Benefit obligation:
Discount rate	3.95%	4.95%	4.05%
Salary increase rate	2.00%	3.00%	3.00%
Net periodic pension cost:
Discount rate	4.95%	4.05%	4.40%
Salary increase rate	3.00%	3.00%	3.00%
Amortization period in years	3 years 11 months 12 days	2 years 11 months 27 days	3 years

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=35743120&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=35743120&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=35743120&loc=d3e1928-114920

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