Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Estimated annual effective tax rate (as a percent)	24.00%	26.00%	23.00%
Income Tax Disclosure
Tax benefit for settlement of stock-based compensation awards	$ 12	$ 43
Tax Year Prior Years
Income Tax Contingency
Income tax examination, proposed liability increase/(decrease)	$ 2,300

Income Tax Contingency

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- Definition

The amount of taxing authority proposed additional income tax and penalty for prior years.

+ References

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- Definition

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
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319

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Amount of tax benefit from exercise of option under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=SL79508275-113901

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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