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.

No definition available.

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- Definition

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 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ 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 (d)(5)(i)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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RETIREMENT AND POSTRETIREMENT BENEFIT PLANS - FAIR VALUE OF PENSION PLAN ASSETS (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	$ 403	$ 386	$ 384
Common and preferred stocks
Defined Benefit Plan Disclosure
Target allocation of plan assets (as a percent)	65.00%
Common and preferred stocks \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	$ 188	178
Debt securities
Defined Benefit Plan Disclosure
Target allocation of plan assets (as a percent)	35.00%
Total pension plan assets \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	$ 411	389
U.S. government securities \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	12	13
Corporate bonds \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	83	85
Common/collective trusts \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	20	18
Bond funds \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	19	18
Blend funds \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	59	48
Other \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	30	29
Net Payables \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	8	3
Level 1 \| Common and preferred stocks \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	188	178
Level 1 \| Total pension plan assets \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	278	257
Level 1 \| U.S. government securities \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	12	13
Level 1 \| Bond funds \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	19	18
Level 1 \| Blend funds \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	59	48
Level 2 \| Total pension plan assets \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	133	132
Level 2 \| Corporate bonds \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	83	85
Level 2 \| Common/collective trusts \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	20	18
Level 2 \| Other \| Pension Benefits
Defined Benefit Plan Disclosure
Fair value of plan assets	$ 30	$ 29