Other Comprehensive Income Information (Schedule Of Income Tax (Expense)/Credit For Components Of Other Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Other Comprehensive Income Information Tax [Abstract]
Foreign exchange translation adjustment	$ 57	$ 1	$ 72	$ 1
Postretirement benefits reserves adjustment (excluding amortization)	74	(56)	64	(36)
Amortization and settlement of postretirement benefits reserves adjustment included in net periodic benefit costs	(62)	(50)	(177)	(152)
Total	$ 69	$ (105)	$ (41)	$ (187)

Amount of tax expense (benefit) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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- Definition

Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

+ References

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

+ References

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- Definition

Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity.

+ References

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