Income Taxes (Provision) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Taxes
2017 Tax Act estimated transition taxes		$ 120
Income tax benefit		16
BEAT liability expense	$ 21	$ 33
2017 Tax Act income tax expense			$ 66

Amount of reasonable estimate for income tax benefit for which accounting for tax effect for remeasurement of deferred tax liability from change in tax rate is incomplete pursuant to Tax Cuts and Jobs Act.

No definition available.

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- References

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- Definition

Amount of income tax benefit for remeasurement of deferred tax liability from change in tax rate pursuant to Tax Cuts and Jobs Act.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319

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- Definition

Amount of income tax expense (benefit) for remeasurement of deferred tax from change in tax rate pursuant to Tax Cuts and Jobs Act.

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- Definition

Amount of income tax expense from transition tax on accumulated earnings of controlled foreign corporation deemed repatriated pursuant to Tax Cuts and Jobs Act.

+ References

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