Income Taxes (Schedule of Reconciliation of Income Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Uncertainties [Abstract]
Tax provision at U.S. statutory rate	$ 29	$ 24	$ 71
Permanent differences and other	1	4	10
State income taxes, net of federal benefit	9	19	11
Income attributable to noncontrolling interest	0	1	1
Change in investment and foreign tax credits	0	6	(8)
Change in U.S. tax law	0	0	(316)
Change in valuation allowance	0	(4)	1
Total tax provision (benefit)	$ 39	$ 50	$ (230)

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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