Stock-Based Compensation - RSUs and PSUs, Other Disclosures (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
RSUs and PSUs
Stock-Based Compensation
Tax benefits realized in connection with vesting and release of awards	$ 139	$ 131	$ 117
Restricted Stock Units
Stock-Based Compensation
Fair value of stock units granted	1,220	674	583
Fair value of stock units vested	$ 478	428	381
Performance Share Units
Stock-Based Compensation
Vesting period	3 years
Fair value of stock units granted	$ 186	164	118
Fair value of stock units vested	$ 86	$ 118	$ 101

The total fair value of granted units.

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

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-Section 50
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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.

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