LEGAL PROCEEDINGS, COMMITMENTS AND CONTINGENCIES - Changes in the Reserve for Asset Retirement Obligations (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Loss Contingencies [Line Items]
Reserve balance as of December 31, 2013	$ 54us-gaap_AssetRetirementObligation
Reserve charges and adjustments, net	10
Payments	(10)
Other adjustments(1)	(14)
Reserve balance as of December 31, 2014	$ 40us-gaap_AssetRetirementObligation

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Asset Retirement Obligation

-URI http://asc.fasb.org/extlink&oid=6505190

+ Details

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- Definition

Amount of cash paid during the period to settle an asset retirement obligation. Amounts paid to settle an asset retirement obligation are generally included in the operating section of the Statement of Cash Flows.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 17

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3367-108585

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- Definition

Amount of asset retirement obligations incurred during the period.

+ References

+ Details

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- Details

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- Definition

Amount of the Increase or Decrease in the amount of asset retirement obligations for the period associated with other adjustments.

+ References

No definition available.

+ Details

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