Postretirement Benefits (Narrative) (Details) - Other Postretirement Benefits Plan [Member] - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Total recognized in other comprehensive income	$ 1
Total recognized in net periodic benefit cost or OCI	12	$ 29	$ (25)
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Total recognized in other comprehensive income	(1)
Total recognized in net periodic benefit cost or OCI	$ 0	$ 9	$ 5

Amount, before tax, after reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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