Income taxes disclosure.

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Increase (Decrease) In Effective Income Tax Rate, Percent

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

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Percentage 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 changes in the income tax rates.

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations.

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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 tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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Amount awarded from other party in judgment or settlement of litigation.

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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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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from tax credit carryforwards for which it is more likely than not that a tax benefit will not be realized.

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Amount of unrecognized tax benefits.

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Income Taxes - Narrative (Details) - USD ($) $ in Millions		12 Months Ended
Income Taxes - Narrative (Details) - USD ($) $ in Millions	Jan. 18, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes Disclosure [Line Items]
Increase in effective income tax rate		1.00%
Effective income tax rate		21.00%	20.00%	11.00%
Effect of revaluation of deferred taxes		0.00%	0.00%	20.00%
Valuation allowance related to tax credit carryforwards		$ 4	$ 6
Excess tax benefits		11	11	$ 7
Employment tax credit disallowed		7	5	4
Unrecognized tax benefits		7	6	$ 6	$ 1
State and Local Jurisdiction
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards		53	61
State tax credit carryforwards		6	$ 7
Internal Revenue Service
Income Taxes Disclosure [Line Items]
Employment tax credit disallowed		11
Income tax examination, penalties and interest expense		4
Recovery of disallowed tax credits	$ 15
2019 Equity Incentive Plan
Income Taxes Disclosure [Line Items]
Excess tax benefits		$ 8