Stockholders' Equity (Schedule of Treasury Stock) (Details) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended	173 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022
Class of Stock [Line Items]
Shares repurchased	0	3,394,548	69,324,429
Average purchase price per share	$ 0	$ 147.30	$ 83.71
Shares repurchased (in $ millions)	$ 0	$ 500	$ 5,803
Aggregate Board of Directors repurchase authorizations during the period (in $ millions)	$ 0	$ 0	$ 6,866

Amount of stock repurchase plan authorized in the period.

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- Definition

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.

+ References

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
-Paragraph 1
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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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