Comprehensive Income (Loss) (Narrative) (Details) $ in Millions	6 Months Ended
Jun. 30, 2020 USD ($)
Comprehensive Income (Loss) [Abstract]
Remeasurement charge	$ 672
Pension settlement costs, net of tax	$ 159

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

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