Income Taxes - Undistributed Earnings and Foreign Location Information (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income tax benefits attributable to reduced tax rates or exemptions in foreign locations	$ 204	$ 163	$ 127
EPS impact of reduced tax rates or exemptions in foreign locations (in dollars per share)	$ 36	$ 28	$ 22
Previously undistributed earnings from non-U.S. subsidiaries permanently reinvested	$ 17,700
Reinvested earnings that may be repatriated from non-U.S. subsidiaries	5,500
Undistributed earnings from non-U.S. subsidiaries permanently reinvested	$ 12,200

Amount of undistributed earnings of foreign subsidiaries which can be repatriated to the country of domicile.

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Previous amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

+ References

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The amount of income taxes from which a reporting entity is exempt or for which it will receive a reduction in income taxes as a result of the income tax holiday granted by the taxing jurisdiction.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330215-122817

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Per share amount effect of the income tax benefit resulting from the income tax holidays granted by taxing jurisdictions.

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Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 740
-Section 50
-Paragraph 1
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 25
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=123452999&loc=d3e28200-109314

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