Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Effective income tax rate reconciliation, percent	21.30%	24.50%	22.40%	24.50%
Discrete tax expense (benefit) related to excess tax benefits from stock based compensation	$ 5	$ 4	$ 12	$ 9
Potential decrease in unrecognized tax benefits	$ 40		$ 40

Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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-Publisher FASB
-Name Accounting Standards Codification
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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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-Paragraph 12
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Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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