Pension and Postretirement Plans (Projected Benefit Obligation in Excess of Plan Assets) (Details) - Pension Benefits - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
United States
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligations	$ 2,730	$ 3,043
Fair value of plan assets	2,377	2,751
Int’l.
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligations	365	1,209
Fair value of plan assets	$ 182	$ 972

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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/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=108410482&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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