PENSION AND POST-RETIREMENT PLANS - ASSET ALLOCATION (Details) - plan	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Employee benefit plans
Number of single-employer defined benefit pension funded plans	2
Qualified Pension Benefits
Employee benefit plans
Target allocation (as a percent)	100.00%
Asset allocations (as a percent)	100.00%	100.00%
One year returns (losses) on plan assets (as a percent)	(2.00%)
Three year returns (losses) on plan assets (as a percent)	8.00%
Five year returns (losses) on plan assets (as a percent)	6.80%
Long-term average return on plan assets since inception (as a percent)	8.30%
Qualified Pension Benefits \| Domestic equity securities
Employee benefit plans
Target allocation (as a percent)	53.00%
Asset allocations (as a percent)	62.00%	63.00%
Qualified Pension Benefits \| International equity securities
Employee benefit plans
Target allocation (as a percent)	15.00%
Asset allocations (as a percent)	13.00%	14.00%
Qualified Pension Benefits \| Debt securities
Employee benefit plans
Target allocation (as a percent)	22.00%
Asset allocations (as a percent)	18.00%	17.00%
Qualified Pension Benefits \| Real estate
Employee benefit plans
Target allocation (as a percent)	5.00%
Asset allocations (as a percent)	6.00%	5.00%
Qualified Pension Benefits \| Other and cash
Employee benefit plans
Target allocation (as a percent)	5.00%
Asset allocations (as a percent)	1.00%	1.00%

The percentage of five-year returns (losses) on pension plan assets.

No definition available.

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- Definition

The percentage of long-term average return on pension plan assets.

+ References

No definition available.

+ Details

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- Definition

The percentage of one-year returns (losses) on pension plan assets.

+ References

No definition available.

+ Details

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- Definition

The percentage of three-year returns (losses) on pension plan assets.

+ References

No definition available.

+ Details

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- Definition

Represents the number of single employer defined benefit pension funded plans.

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

+ Details

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Details

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