PENSION PLANS AND OTHER POSTRETIREMENT BENEFITS (Other Post Retirement Benefits) (Details)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate - benefit obligations	3.51%	3.88%
Discount rate - net periodic costs	3.88%	4.08%	3.75%
Health Care Cost Trend Rate Assumed Next Year - benifit obligations	6.75%	7.00%
Health Care Cost Trend Rate Assumed Next Year - net periodic costs	7.00%	7.25%	7.05%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate	5.00%	5.00%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate To Calculate Net Period Benefit Cost	5.00%	5.00%	5.00%
Year that Rate Reaches the Ultimate Health Care Cost Trend Rate	2025	2025	2020
Defined Benefit Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate - benefit obligations	3.59%	4.00%
Discount rate - net periodic costs	4.00%	4.26%	3.90%

Defined Benefit Plan, Health Care Cost Trend Rate Assumed to Calculate Net Periodic Benefit Cost, Next Fiscal Year

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- Definition

Defined Benefit Plan, Ultimate Health Care Cost Trend Rate To Calculate Net Period Benefit Cos

+ References

No definition available.

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit 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=82843861&loc=d3e1928-114920

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status.

+ 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 (l)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Ultimate trend rate for health care cost for defined benefit postretirement 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 (l)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Year ultimate health care cost trend rate is expected to be reached, in CCYY format.

+ 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 (l)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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