Pension and Postretirement Plans (Projected Benefit Obligation in Excess of Plan Assets) (Details) - Pension Benefits - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
United States
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligations	$ 3,148	$ 2,730
Fair value of plan assets	2,702	2,377
Int’l.
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligations	419	365
Fair value of plan assets	$ 207	$ 182

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2417-114920

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- Definition

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

+ References

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