Amounts in Paragraphs - Income Taxes (Details 5) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Effective income tax rate	14.50%	11.80%	13.70%
Significant matters affecting comparability	(1.30%)	(3.70%)	(1.10%)
Increase in Research Tax Credit		$ 30	$ 12
Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act, Amount	$ 0	0	(84)
Income taxes paid, net	312	324	$ 270
Tax Credit Carryforward, Amount	419
Operating Loss Carryforwards	364
Tax Credit Carryforward, Valuation Allowance	221
Operating Loss Carryforwards, Valuation Allowance	31
Income Taxes Receivable	$ 792	$ 551

Effective Income Tax Rate Reconciliation, Increase in Research Tax Credits

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740-10-50-14. If not otherwise evident from the disclosures required by this Section, all entities shall disclose the nature and effect of any other significant matters affecting comparability of information for all periods presented.

+ References

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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operations, attributable to Tax Cuts and Jobs Act.

+ References

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Carrying amount as of the balance sheet date of income taxes previously overpaid to tax authorities (such as U.S. Federal, state and local tax authorities) representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Also called income tax refund receivable.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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

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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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