(Pension Benefit Adjustments Recognized In Other Comprehensive (Loss) Income) (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Current year actuarial (gain) loss	$ (89)
Amortization of actuarial loss	(200)
Current year prior service cost	40
Amortization of prior service cost	(16)
Settlements/curtailments	0
Total recognized in other comprehensive income	(265)
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Current year actuarial (gain) loss	19
Amortization of actuarial loss	(2)
Amortization of prior service cost	0
Settlements/curtailments	(1)
Effect of foreign currency exchange rate movements	2
Total recognized in other comprehensive income	$ 18

Other Comprehensive Income, Other Pension and Postretirement Plans, Foreign currency (loss) gain

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Amount, before tax, of cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

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Amount, before tax, of increase (decrease) to other comprehensive income from settlement and curtailment gain (loss) of defined benefit plan.

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