Equity (Share Repurchases) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Equity [Abstract]
Number of shares repurchased	16	0	32	0
Cash paid for shares repurchased	$ 928	$ 0	$ 1,912	$ 0
Average cost per share	$ 58.78	$ 0	$ 60.91	$ 0

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- Definition

The cash outflow to reacquire common stock during the period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

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