Stockholders' Equity Table Of Reclassifications from AOCI (Details) - Reclassification out of Accumulated Other Comprehensive Income [Member] $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax benefit	$ (2)
Reclassifications during the period	8
Pension and Other Postretirement Benefits
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of actuarial (gain) loss and net actuarial loss from settlements included in net periodic benefit cost (credit)	$ 10

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

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