Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Net operating loss carry-forwards		$ 152
Deferred income taxes	$ 679	681
Total tax (benefit) provision	$ 39	$ 50	$ (230)
Federal income tax rate	21.00%	35.00%
Change in U.S. tax law	$ 0	$ 0	$ (316)

Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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