Goodwill and Other Intangibles (Changes in the Carrying Amount of Goodwill) (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Goodwill [Roll Forward]
Balance as of January 1,	$ 15,517	$ 14,671
Goodwill acquired	374	462
Other adjustments	(243)	(99)
Balance at September 30,	$ 15,648	$ 15,034

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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