Stockholders' Equity Table Of Reclassifications from AOCI (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Noncontrolling interest	$ 19	$ 118
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax benefit	(1)
Reclassifications during the period	3
Reclassification out of Accumulated Other Comprehensive Income [Member] \| Pension and Other Postretirement Benefits
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of actuarial (gain) loss included in net periodic benefit cost (credit)	$ 4

Amount of Net Income (Loss) attributable to noncontrolling interest.

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