EMPLOYEE RETIREMENT PLANS - Defined-benefit Pension Plans with an Accumulated Benefit Obligation in Excess of Plan Assets (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Qualified
Information for the defined-benefit pension plans with an accumulated benefit obligation in excess of plan assets
Projected benefit obligation	$ 882	$ 945
Accumulated benefit obligation	882	945
Fair value of plan assets	655	679
Non-Qualified
Information for the defined-benefit pension plans with an accumulated benefit obligation in excess of plan assets
Projected benefit obligation	155	170
Accumulated benefit obligation	155	170
Fair value of plan assets	$ 0	$ 0

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- Definition

Amount of accumulated benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2417-114920

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- Definition

Fair value of plan assets for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

+ References

+ Details

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- Definition

Amount of projected benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=77993564&loc=d3e4179-114921

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