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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.

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No definition available.

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Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 30
-Section 35
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Plan Assets
-URI http://asc.fasb.org/extlink&oid=6749337

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Plan Assets
-URI http://asc.fasb.org/extlink&oid=6520858

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- Definition

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

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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EMPLOYEE BENEFIT PLANS - PLAN ASSETS (Details) - Qualified Defined Benefit [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Plan asset allocations	100.00%	100.00%
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Plan Assets	$ 2,083	$ 1,846	$ 1,737
Level 1 [Member]
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Plan Assets	$ 1,973	$ 1,752
Equity funds [Member] \| U.S.
Defined Benefit Plan Disclosure [Line Items]
Plan asset allocations	25.00%	30.00%
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Equities, Range Minimum	5.00%
Equities, Range Maximum	33.00%
Equity funds [Member] \| U.S. \| Level 1 [Member]
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Plan Assets	$ 515	$ 545
Equity funds [Member] \| Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan asset allocations	11.00%	12.00%
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Equities, Range Minimum	1.00%
Equities, Range Maximum	16.00%
Equity funds [Member] \| Non-U.S. [Member] \| Level 1 [Member]
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Plan Assets	$ 226	$ 218
Credit bond index fund [Member] \| Level 1 [Member]
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Plan Assets	$ 1,232	$ 989
Fixed Income Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan asset allocations	59.00%	53.00%
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Equities, Range Minimum	48.00%
Equities, Range Maximum	95.00%
Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan asset allocations	4.00%	5.00%
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Equities, Range Minimum	2.00%
Equities, Range Maximum	8.00%
Real Estate [Member] \| Level 3 [Member]
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Plan Assets	$ 97	$ 91
Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan asset allocations	1.00%	0.00%
Cash Equivalents [Member] \| Level 1 [Member]
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Plan Assets	$ 13	$ 3