Stock-Based Compensation - Schedule of Restricted Stock and Unit Activity (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Tax benefit relating to restricted award activity	$ 32	$ 38	$ 20
Restricted Stock and Unit Awards
Shares
Beginning Balance (in shares)	1.6
Granted (in shares)	0.6
Vested (in shares)	(0.8)
Forfeited (in shares)	0.0
Ending Balance (in shares)	1.4	1.6
Total unrecognized compensation expense related to restricted awards	$ 159
Weighted-average years to be recognized over	1 year 2 months 12 days
Weighted-average grant-date fair value
Beginning balance (in dollars per share)	$ 364.50
Granted (in dollars per share)	374.00	$ 384.65	$ 296.49
Vested (in dollars per share)	388.31
Forfeited (in dollars per share)	325.24
Ending balance (in dollars per share)	365.51	364.50
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Weighted-average grant-date fair value per award (in dollars per share)	$ 374.00	$ 384.65	$ 296.49
Total fair value of restricted stock and other stock-based awards vested	$ 323	$ 146	$ 243
Tax benefit relating to restricted award activity	$ 71	$ 30	$ 48

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Section 50
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-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Name Accounting Standards Codification
-Section 50
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-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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