EMPLOYEE BENEFIT PLANS - 1% HIGHER OR LOWER TREND RATE IN HEALTH CARE (DETAILS) (Postretirement Medical Benefits [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Postretirement Medical Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Change in service and interest cost, 1% higher trend rate	$ 1	$ 1	$ 2
Change in service and interes cost, 1% lower trend rate	(1)	(1)	(1)
Change in year-end postretirement benefit obligation, 1% higher trend rate	9	10	14
Change in year-end postretirement benefit obligation, 1% lower trend rate	$ (8)	$ (9)	$ (12)

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Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ 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 (m)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

+ Details

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

+ Details

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ References

+ Details

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

+ Details

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