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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
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-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, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Plan asset allocations	100.00%	100.00%
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Plan Assets	$ 1,846	$ 1,737	$ 1,917
Level 2 [Member]
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Plan Assets	$ 1,755	$ 1,652
Equity funds [Member] \| U.S.
Defined Benefit Plan Disclosure [Line Items]
Plan asset allocations	30.00%	28.00%
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Equities, Range Minimum	22.00%
Equities, Range Maximum	33.00%
Equity funds [Member] \| U.S. \| Level 2 [Member]
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Plan Assets	$ 545	$ 491
Equity funds [Member] \| Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan asset allocations	12.00%	12.00%
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Equities, Range Minimum	9.00%
Equities, Range Maximum	16.00%
Equity funds [Member] \| Non-U.S. [Member] \| Level 2 [Member]
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Plan Assets	$ 218	$ 208
Credit bond index fund [Member] \| Level 2 [Member]
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Plan Assets	$ 992	$ 953
Fixed Income Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan asset allocations	53.00%	55.00%
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Equities, Range Minimum	48.00%
Equities, Range Maximum	67.00%
Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan asset allocations	5.00%	5.00%
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Equities, Range Minimum	0.00%
Equities, Range Maximum	8.00%
Real Estate [Member] \| Level 3 [Member]
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Plan Assets	$ 91	$ 85